Should I attempt to uninstall Android bloatware? Android storage explained (or part of it)

There is a significant number of posts on the internet regarding how people hate bloatware that comes bundled with their devices, how it eats at their precious internal storage space and how they would want to uninstall it (which is impossible w/o rooting your device). While I agree with one’s right to hate the bloatware, everything else is a delusion. Let’s take a look.


How Android measures WLAN signal strength

Ever wondered how Android decides how many bars to show in the WLAN indicator? (Well, the “bars” are gone, but there’s still exactly the same number of levels) While going through Android source code  I’ve found this:


* RSSI levels as used by notification icon
* Level 4  -55 <= RSSI
* Level 3  -66 <= RSSI < -55
* Level 2  -77 <= RSSI < -67
* Level 1  -88 <= RSSI < -78
* Level 0         RSSI < -88


/** Anything worse than or equal to this will show 0 bars. */
private static final int MIN_RSSI = -100;

/** Anything better than or equal to this will show the max bars. */
private static final int MAX_RSSI = -55;

So, now you know! Of course, vendors may change these values, but let’s hope they don’t! 🙂

Why is this important? This the basis of Android’s Poor Link Detection Watchdog – the thing that causes your WLAN clients to switch to another WLAN profile or to WWAN entirely when you least expect it. But I haven’t grok’d all the code yet. Stay tuned…

Bypassing Android security via backups (PSK recovery)

In my recent Android trainings and the Android security talk I gave at AppForum 2014 I was asked to provide a sort of a demo that can be easily replicated to explain the importance of maintaining a proper security posture. So I created a script that ‘recovers’ PSKs from the device and displays them.

Before moving on, a brief disclaimer: Android (or iOS, or Windows) are pretty secure, it is up to the user how much of this security is traded for convenience (or ignorance).


Harnessing Android Intents

This post is about Android Intents, and how to use them to start/stop/show/hide Android apps and services and perform some more advanced actions. Intents are the glue that binds numerous Android components together, and are very important for understanding and mastering various aspects of Android. Main goal of this guide is to understand enough about intents in order to be able to use them in ADB scripts and other tools that allow sending Intents.


Android multiuser model architecture and related security threats

Android-HolesI have recently bumped into a very interesting research article called “A Systematic Security Evaluation of Android’s
Multi-User Framework” and want to leave here a digest and some of my analysis in the aspect of Enterprise use. I recommend reading the paper for more details, it’s only 10 pages. The more I learn of Android, the more it reminds me of a cheese grater (other OSes are no better). This doesn’t include any of Android L enhancements, as those are not officially released yet.