Category: Android

Advanced geolocation plugin for Cordova and PhoneGap for Android

The W3C’s browser-based, JavaScript Geolocation API is excellent as a one-size-fits-all interface, but that approach comes at a price and it can cause some serious limitations when it comes to implementing more stringent professional, commercial and government use-cases.

Challenges with the default Geolocation API. One of the primary limitations is the Geolocation API does not tell you how it got a location. All locations are lumped together in a black box. Let me explain. On a smartphone or tablet, location data comes from one of three places: the GPS chipset, the cellular provider’s Location Service, or the browser’s Location Service. The W3C Geolocation API simply lumps these data points together. The end result is typically seen by the end user as significant and disturbingly wild jumps back and forth in the reported location, sometimes over large distances. A key to minimizing these fluctuations is to gain back control and understand which location provider created the latitude and longitude point.

Cordova-plugin-advanced-geolocation. The good news is that Android, in particular, has a very detailed API called LocationManager for examining geolocation data that comes from the device.  And, even better news for JavaScript developers is that the API, along with its access to all on-device GPS and Network location providers, has been exposed thru a Cordova plugin that is available here: https://github.com/Esri/cordova-plugin-advanced-geolocation.

What geolocation data is available? With this plugin you’ll be able to programmatically differentiate between the following geolocation data as well as get access to GPS satellites meta data:

  • Real-time GPS location – This is data from the on-board GPS or some devices will allow it to be the location data from an external GPS that is connected to the device via bluetooth.
  • Cached GPS location – Most devices cache the last-known GPS location and it’s persistent even when the device is restarted.
  • Real-time Network location triangulation – this is completely dependent on devices and cellular service providers. It may require WiFi to be turned on. It also may not be available in all countries or regions.
  • Cached Network location – Most devices cache the last-known network-based location and it’s persistent even when the device is restarted.

Use cases. With this plugin, you can now use your JavaScript skills to implement the following use cases and much more. For example, I’ve always wanted to play with the Satellite data to make a 3D map of the satellites using JavaScript. This plugin provides a huge advantage to developers building applications for capturing a single location such as field survey work as well as the following use cases and others that I haven’t thought of:

  • Determine a static outdoors location and only use GPS.
  • While indoors turn on only network location. Do not use GPS.
  • While in an urban area, use network location to get initial location before the GPS warms up and then turn off network location and only use GPS
  • Compare the differences between GPS and Network locations
  • …???

How does this plugin help minimize location fluctuations? This plugin comes with a configuration option for turning on a buffer. You can set the size of the buffer, each new geolocation from the device will be added to it, and then plugin will determine the geometric center based on all the locations in the buffer.

Are there any other advanced plugins? Yes, some Cordova plugins are focused on being activity based and will detect if you are walking, stopped, moving, etc. These plugins tend to work as apps that can be backgrounded. Feel free to browse the Cordova plug-in directory here.

The one thing that Android needs the most

Android has really missed the boat on one thing that iTunes and iCloud do really well. That is the Android eco-system doesn’t have a built-in, seamless solution for restoring a device from scratch.

There is no universal way to backup and restore Android’s home screen and your phone’s application organization, your application data and settings, photos, videos, messages, ringtones, miscellaneous phone settings, etc.

What this means is it’s a pain and potentially time consuming to rebuild your phone or tablet every time you buy a new Android, your current phone dies because you dropped it, or if you have to switch over to a replacement. The issue is further compounded by the fact that some apps prevent you from saving them to an SDCard. I’m not sure if this is intentional or simply an oversight by the developer when they configured the application for uploading to Google Play.

Third party apps have jumped in to try and fill the void. Many take a really good stab at addressing the issue, but the solutions and their features can be a hodge-podge. Some, such as Titanium Backup, require you root your phone which many people are wary of because it voids any warranties. Others, such as App Backup & Restore, aren’t able to back up the application data and that means all your settings are lost.

I would trade a well-done backup and restore functionality from Android for any new gimmicky feature or pseudo-incremental improvement. Universal back up and restore would be a huge bonus for the entire Android community.

Android Privacy Part 2: App Ops & Google Play Improvements

Let me start out by saying I like my Android phones. I like developing for Android even with all the inherent version support issues, etc etc. So, in my previous post I brought up privacy issues related to installing Android apps along with a suggested fix. That post was inspired by a major change in Android v4.4.2 that removed “App Ops,” even though I didn’t mention it by name. The removal of that functionality is now a very visibility topic thanks to a number of high–profile bloggers such as the Electronic Frontier Foundation (EFF) who also have taken exception to this change.

In a nutshell, App Ops or its equivalent, would allow you to manually toggle individual application permissions on and off.  You can search for articles on what App Ops is, or read my previous post on what it should be.

I’d take the issue of “control over what applications can access” even one step further and propose that it’s well past time that Google should begin reviewing Android app submissions similar to what Apple does for the App Store.  Seriously. In combination with App Ops, or similar functionality, this could only help reduce the amount of nefarious practices, content, viruses, Trojans and more. Case-in-point: for the first this September, Kaspersky Labs reported a particularly sophisticated Trojan virus along with distribution mechanisms specially gift wrapped just for Android users. And, then again in November they announced an Android-specific financial phishing Trojan aimed at stealing banking usernames and passwords.

To get an idea of what is allowed on Google Play all you need to do is compare Apple’s App Review Guidelines with Google Play Policies and Guidelines. For example, searching the related Android Developer Content Policy for the term “review”, it only shows up once, and that is in regards to serving up advertisements.

My hope is that Google takes heed and makes some necessary and timely changes so that we can all continue to enjoy our Android devices safely and securely.