Posts

Visually Classifying Your Maps by Attributes

Tired of staring at the same, drab, mess of lines and polygons? Having trouble finding the shapes you want? Mappt now has support for Classifications, allowing you to style your features according to the numeric or text values in the layer’s attributes.

Here we have some geological zones. As is typical with datasets, it’s not very pretty to look at. Worse, we can’t really tell much by just glancing at it!

Mmm, red.

Mmm, red.

Looking at the attributes defined in the layer, we can see there is an AREA key defined.

The list of attributes values for one of the zones.

The list of attribute values for one of the zones.

Let’s say we want to easily see the zones with the smallest areas. To do this, we open the layer’s properties, then navigate to the Classifications tab. Here, we can specify how we want to classify the data. In this case, we want to find highlight the features with the smallest AREA attribute value. Let’s do some experimenting!

First, we’ll try to classify the AREA by “Distinct Values”, which will give us a class for every unique AREA value in the layer.

The Classifications screen, showing how to classify an attribute by Distinct Value.

The Classifications screen, showing how to classify by Distinct Value.

When we hit Apply, the classes are generated, and we are taken to the Class Styles tab, which shows the styling applied to each of the determined classes. In the screenshot below, we can see that there were quite a few unique values, so much so that we haven’t really achieved anything by classifying them!  Perhaps Distinct Values wasn’t such a great choice!

There are too many classes to fiddle with.  We can see that classifying a numeric attribute by Distinct Value was a bad idea!

There are too many classes to fiddle with. We can see that classifying a numeric attribute by Distinct Value was a bad idea!

Let’s try again, this time using “Equal Intervals”, which instructs Mappt to classify the features into x number of classes, with x being chosen by us. So, let’s try Equal Intervals.

Let's try that again, this time with Equal Intervals.

Let’s try that again, this time with Equal Intervals.

This will give us 5 nice classes, evenly spread across the range of values found in the AREA attribute of the features in the layer.  We can apply styling to each class, as seen in the screenshot below, where I have used the colour blue to denote the lowest-range class, and yellow for the rest.  Also note that Mappt shows us the range of each class, as well as how many feature are in it, which is handy when fine-tuning your classification parameters.

Geology zones classification equal styles

Highlighting the lower-fifth zones by area in blue.

Closing the layer properties dialog, we can see the styling has been applied to the map. Because of the settings we choose, we have effectively highlighted, in blue, the zones that are in the lower 20% of overall zone sizes.

The smallest fifth of the zones, by area, can now easily be seen!

The smallest fifth of the zones, by area, can now easily be seen!

Using another example, here I have taken a dataset of the world’s volcanoes and classified them by elevation, using Manual Breaks defined at -4000, -2000, 0, 2000 and 4000 feet, allowing me to see which volcanoes are the highest, with increasing blue being below sea level, and increasing red being above sea level.

Blue because water is blue, red because... just because.

Blue because water is blue, red because… just because.

On the map, we can easily see which volcanoes are above or below sea level, as well as how far above or below, simply from their colour.

Aloha!

Aloha!

One last example shows the path of hurricanes in the Atlantic, coloured by wind speed, with redder being faster.

Red always gets such a bad rap in these things.

Red always gets such a bad rap in these things.

So in summary:

Classifications: Mappt, pretty.

Top Three Android tablets for Field use with Mappt.

When using Mappt in the field there are two main requirements.

1: Mappt

2: Awesome Android tablet

Mappt we can provide, but you will have to take care of the Tablet part. This is in fact the harder of the two tasks as there are hundreds of Android tablets to choose from. If you are like most people they will all look pretty similar so in the end it will come down to price. The cost of the device is a major factor in it being selected, but you should take a good close look before you buy. In this article we will try to aid you in this task. To select a tablet not only on it’s looks or price but also by the many other factors such as available accessories, stability, size, weight and most importantly durability for field use.

Tablet 1

Nexus 7 (gen 2)

The Nexus 7 is the third Android tablet in the Nexus line and co-developed by Google and ASUS. It’s a very powerful small form tablet with a lot of accessories.

The New Google / ASUS Nexus 7 gen 2

The New Google / ASUS Nexus 7 gen 2

Tablet 2

Sony Xperia Z

In February 2013 SONY unveiled it’s new tablet the Xperia Tablet Z. A 10 inch tablet that is light, weighing just under half a kilogram and less than 7mm thick.  It’s the worlds thinnest 10 inch tablet not to mention it’s IP55 and IP57 (Ingress Protection) rating making it dust proof, scratch resistant and water proof up to 1 meter for up to 30 minutes.

The Xperia Tablet Z's ports are all well covered and protected against dust and water ingress.

The Xperia Tablet Z’s ports are all well covered and protected against dust and water ingress.

Tablet 3

Panasonic Toughpad FZ-A1

Our final contender is the Panasonic Toughpad FZ-A1. The ultimate field partner. It’s Military spec all weather proof at IP65 and drop proof at 4 feet making it virtually indestructible as far as tablets are concerned. Unfortunately this is also reflected in the price tag.

 

 

All ports are covered and locked away from the elements making this tablet an impregnable bunker.

All ports are covered and locked away from the elements making this tablet an impregnable bunker.

 

Below is a table that compares the three tablets as well as a short review based on Mappt use.

Top three Mappt Field Companion Android Tablets, and why.

Top three Mappt Field Companion Android Tablets, and why.

The Mappt Advantage

 

Nexus 7 gen 2 (4G LTE)

Being the lightest of the three tablets this is in itself a big advantage. Not to mention that it’s fast, powerful and has a highrez display with very good battery life.The price is also very enticing, although you will need to get some very necessary accessories, such as a tough case, matte screen protector, car charger, etc.

Using Mappt on this tablet you are able to conduct all your usual tasks at a very acceptable speed, even with the smaller form factor. This is actually one of its biggest advantages.

An excellent compact Mappt companion that won’t hurt your pocket and fits right in it.

 

Sony Xperia Tablet Z  (4G + WIFI 16gig)

The new Sony Xperia tablet Z has taken the world by storm with its very durable shell, water proof for 30 minutes, dust proof and only 6.9mm thin. A very well rounded tablet with plenty of available accessories, not that you would need any to start off except perhaps a car charger. Perfect as a Mappt companion.

Mappt moves very fast on this device. Information loads lightning fast on the 4G LTE or WIFI. Navigation is a breeze with the clean shatterproof, sensitive, matte screen. Only down side is that it’s a little hard to see the screen in a well sun lit environment. This may be a big issue for some scenarios.

A very well priced and durable tablet. Perfect for almost all you every day Mappt field use.

 

Panasonic Toughpad FZ-A1

If you ignore the huge price tag on this beast then this is hands down the tablet you want with you in the field. Its military spec hardware and case make it literary indestructible (figuratively). You can drop this guy from a height of 2 metres into an ice filled lake and have it sit on the mud lake floor (shallow lake), pick it up moments later and continue working on it.

Mappt works very well on this device even though it runs Android version 4. It has powerful 4G and WIFI connections and a GPS that will never fail. This tablet also comes with a stylus which can help when in the field, so you don’t have to get dirty hands on the screen and have to continuously wipe it.

What it falls short on, which are not vital for Mappt field use, are the cameras and lack of ultra highres display. Also be aware that buying accessories for the Toughpad FZ-A1 will also set you back a bit, as most of the accessories match the higher price of the device.

A tablet for very serious Mappt users who perhaps plan to trek into the caldera of an active volcano.

Loading Tiled Imagery into Mappt

Last week I posted an article about Mappt supporting Compact Cache Bundles but did you know it already supports tiled imagery.  The difference between the two is that tiled imagery is exploded so each tile is it’s own image file.  There are three bit’s of information a tile needs to display on a google map.

  • The Level of Detail (LOD)
  • X position and
  • Y position

Tiling programs generally create a directory hierarchy to define these three properties.

Directory tile hierachy

Here the first directory is the LOD.  The next is the X location and the filename is the Y.   This is the most common structure but occasionally you will come across tiles with a single filename that contains the LOD, X and Y separated by an underscore character:

tile_hierachy_small

Mappt is capable of using both of these tiled images formats.  Just transfer the tiles to the tablet via the USB cable and make note of where they are located.   Personally, I load them into the Mappt -> Downloads folder and use ER File Explorer to  verify the exact path to the tiles.

es_file_explorer_path

Now select ‘Tiled Map Layer’ from the ‘Add/Load layer dialog’.

select_tiled_map_layer

Enter a name for the new layer and then type in the path to the tiles.

add_tiled_map_layer

The important part here is the fields surrounded by the curly brackets ‘{zoom}/{x}/{y}.png’ .  This part defines the structure of the tiles as discussed above.

Mappt now supports ArcGIS Compact Cache Bundles

We are pleased to announce that Mappt now supports ArcGIS Compact Cache Bundles.

Loading in your own satellite imagery is a common feature request for Mappt  and it’s not hard to see why.  Accessing your own imagery from a tablet gives GIS professionals and field workers the unprecedented power of being able to stand inside their data and perform ground surveys and analysis with total confidence they are looking at the correct features.  The inclusion of Compact Cache bundles is one of several new features that allows loading of custom imagery into Mappt and at the time of writing we are the only option outside of ESRI to utilize this format.  Mappt has been tested on the Sony XPeria Z with 30Gb of imagery and we have found the only limitation is the amount of free space on the SD card.

Mappt with a Compact Cache Bundle of ASTER satellite imagery.

Mappt with a Compact Cache Bundle of ASTER satellite imagery.

Compact Cache Bundles are a convenient format for tiled Imagery.   The biggest advantage of compact caches over an exploded format is that it eliminates the overhead associated with thousands of little files which means faster file transfer times and less space on disk.  This is a huge deal when transferring several Gigabytes worth of imagery onto a tablet.

Behind the scenes compact cache bundles act like a phone book.

compact_cache_bundle_hieracy

Up to 16,000 tiles for a particular level of detail are conglomerated into a single file with a .bundle extension.  This file has a companion with a .bundlx extension that acts like an address book for tiles.   Looking up the address for a tile has some computational overhead compared to an exploded format but fortunately we were able to optimize it to the point where there is no impact on Mappt’s performance.

Useful apps (from other people) for Mappt users

When developing software, it’s important not to overload with features that the majority of people don’t have a need for. Instead we are working to make the best Android based software for getting your data from the field to the office.

So rather than adding a lot of unnecessary bells and whistles, we have been looking for Play store apps that are either free or low cost and can be useful tools in the field for Mappt users.  We collected a short list below of useful 3rd party apps but will add and update this as we find or are told about apps that can help you do your job.

As these are 3rd party apps we can’t guarantee they will work on your tablet or be supported in the future but all are pretty popular with a good user base.  Any problems or questions about these apps should be directed to the developer

If you have any to add to the list, just let us know and we’ll have a look and if we like them we’ll add them to the list.

So here they are:

Bluetooth GPS (Free)
An absolute necessity if you want to tie in a GPS that’s more accurate than the one found in most tablets.  Just run the app and connect with your Bluetooth enabled GPS and watch the GPS error circle shrink. Mappt automatically uses this signal, overriding the inbuilt GPS. Great price too.

Clinometer + bubble level (Free / $0.99)
Great in built clinometer / level for looking at geological and other structures and saves you carrying an extra tool around but you will have to add the data to Mappt manually.

GPS Status (Free / $3.49)
Great little tool for working out what your GPS and other general locational data including:

  • GPS error (m)
  • GPS satellites with a fix / available
  • Pitch / roll
  • Altitude (MSL)
  • Brightness (lux)
  • Lat / Long
  • Orientation / heading

Unfortunately the free version has the occasional annoying ad at the bottom. The PRO version removes the ads and adds additional features including:

  • show/store/edit multiple waypoints and use them on the Radar for navigation; and
  • pressure, rotation, temperature, humidity values (if device supports them).

If you are also using Bluetooth GPS , this app will show your external GPS error margin but not the satellite fix data.

AirDroid (Free)
Great app for linking your android tablet to a PC over a wireless network (or over the internet) and comes with a number of really useful features including:

  • Desktop SMS Send & receive SMS from the comfort of your computer. Faster typing and navigation with the full keyboard and large screen.
  • Files and Media Move photos, videos, ringtones and any other files on and off Android, all without a USB cable.
  • Find Phone / Device  Locate and lock your Android when it’s lost. Cannot get it back? Simply wipe all data remotely and the innovative intruder feature that takes a photo of the “intruder” who tried but failed to unlock your device.
  • Manage Apps Easier way of app search, installation and apk export.
  • Camera and Screenshot See through the lens of your Android camera, front and back. Or stream the screen of your Android in nearly real-time.
  • Phone Calls, Clipboard , Url transfer and more Call contact, share clipboard content, push url to Android and more features awaiting your discovery.

ES File Explorer File Manager (Free)

Judged by our developers as the best explorer and file manager available for Android it allows easy linking up to Windows based systems all-round the best tool of its type for Android, with over 10 million users, it’s hard to argue with those numbers.

 

Mappt v1.4.2.2 Now Available

We are pleased to announce the release of version 1.4.2.2 of Mappt for Android.

You can download the latest version of Mappt from the Google Play store:

Link to download Mappt from the Google Play store

Read below for the new features in this version!

Apply Style to Layer

This version contains a sorely missed feature – the ability to edit the styling of a vector layer and all features within it.  This is handy when you have loaded a Shapefile that contains hundreds of features, and you would like to make it prettier than the default red.

Picture of the Layer Style Dialog

The new Style tab on the Layer Properties dialog.

Overhauled “Jump To” Dialog

The Jump To dialog has been overhauled and now allows you to jump to any location, in any format, i.e.:

  • Decimal Degrees, e.g. -32.012° 115.507°
  • Degrees-Minutes-Seconds, e.g.  32° 0’46″S 115°30’27″E
  • UTM, e.g. 50 H, 359044 E, 6457171 S
  • Address, e.g. Rottnest Island, Australia
Image of the Jump To dialog in Mappt

The overhauled Jump To dialog.

Bug Fixes

Lastly, we squashed a few bugs in this release and are taking suggestions on good boot-cleaning products.

Don't worry, Mappt has less bugs than this.

Don’t worry, Mappt has less bugs than this.

The Mappt Development Cycle

Software development is easy, but managing software development is hard.  When asked for timelines on feature requests, software developers will offer vague answers such as “soon”, “next release” or the ever-helpful “it’s on the roadmap,” expertly avoiding a definitive answer as well as the best politician.

As Mappt is a new product, feature requests come in thick and fast, much faster than our team of handsome developers can implement.  Because of this, prioritisation becomes key.

All feature requests (and bug requests) made to the Mappt team, be they verbal, written or mimed, are catalogued into our internal “backlog,” to be reviewed, estimated, prioritised and scheduled for implementation at a later date.

When work on the current set of features and bug fixes is complete, the Mappt team sits down at the Table of Meeting and looks through each item in the backlog, fleshing out the details and putting an estimate against each one.

The Mappt team meets.

The Mappt team meets.

Each item is then prioritised against the others, giving us a rough “order of implementation.”  We then calculate how much developer time we have to address these items, based on developer availability, as well as set a target date for implementation.  From these figures, we can confidently determine exactly which items will be implemented (and bugs fixed) by the target date.  The team as a whole agrees to the defined set of work, making a promise to deliver on-time, and pets are given up as collateral.

This is all roughly based on the principles of the Agile method of software development.

The whole process usually takes anywhere from 2 to 6 weeks, depending on the urgency of publishing a new version to the Google Play store.  This means that at the time a feature request comes in, even in ideal circumstances, it may be a few months before it finds its way into a public Mappt build.

Of course, there are always exceptions.  In cases where items are critical to client needs, we can accelerate development or offer custom builds.  We consider these types of situation on a needs basis, so feel free to contact any of the team if you need some special love.