Android developer mode tools

Having basic knowledge about the work with various Android devices, you can always optimize your work. Even understanding the work principle of various functions, QA-engineers continue to make small mistakes which often influence time or quality metrics on the project.

First of all it’s important to learn basic terms and principles, simultaneously defining main mistakes, which can appear during the work with the system.

Android Developer Mode is the special system function, activating which provides access to additional possibilities and OS settings. Among them there are an auxiliary functions for work with device hardware and software, developer tools, logging and system diagnosis, and also many other useful operations.

It means that almost all, interesting for you, inner functional system activity is unavailable by default.

Often, the developer mode tools are unknown for the regular user, because it’s mainly intended for IT sphere workers: app developers, OS versions included, testers and service masters. But there are cases when the user also needs to use this function. It happens, for example, when there is a need to use USB debugging, allow unblocking the downloader or show the tap on the device screen (if user actions should be displayed).

Developer mode is built-in to the Android system starting from the 4th version (Kitkat) and to all newer versions.

Steps to open Android developer mode:

1. Tap the «Settings» menu item - «Phone details» (or «About phone» - depends on OS version and placed mainly at the end of the list).
2. Quick tap the «Build number» menu item (or «Kernel version») about 5-10 times.

In this case, if everything is done correctly, «You become a developer» notification will be displayed. Then the «Developer options» menu item appears in the device settings. Further, we will look through this functional part of the system.

Even at this stage it’s possible to optimize your work, making the shortcut for the certain tab of the device settings (Shortcut Creator). When the task often is performed on a certain device, such little things and preparations reduce time spent on the repeated checks.

When turning on the developer mode, it’s very possible that the user will be asked to enter a password or graphical key. In this case you should enter the password that is used for unblocking the device. In certain cases «0000», «1111».
combinations fit well.

Developer settings

Developer settings are chosen due to the requirements and consist of different sections, which also are divided into subsections.

• Bug report:
  • Interactive - allows to get additional information about the issue, take a screenshot, track the bug report status.
  • Detailed - for cases when the device has become slow during working or doesn’t respond to the commands.
• Backup password: allows to change the data backup password to secure the system data.
• Stay awake: screen stays not blocked (lighted up) if the device is charging.
• Bluetooth HCI snoop log: all Bluetooth HCI data will be stored in the BTSNOOP_HCI.log log-file (file path will be different depending on smartphone and OS version). Data from this log-file can be investigated with special software.
• OEM unlock: allows to enable and unable OS downloader unblocking on those devices where it’s blocked. Activation is needed, for example, to install unofficial firmware.
• Running services (processor statistics): allows to look through all active apps, also ones that launched in the background mode, and receive the information about RAM usage and working time.
• Picture color mode: possibility to switch to sRGB color scheme.
• WebView implementation and Multiprocess WebView: opens links in apps without the help of browsers. Useful for apps, which don't have browser functions.
• Auto update system: turn on/off. Activation of the OS updates search and its components, their installation after device restarting.
• Demo mode: during activating this mode system displays 100% charge, full network strength and Wi-Fi signal.

Debugging

Function list for smartphone work, connected to PC via USB-cable:

• USB debugging: Turn on/off debugging from PC (can be activated after connecting to PC via USB-cable).
• Revoke USB debugging authorizations: used for devices which were early used for the debugging.
• Include bug reports in the power menu: this function is inactive by default. After  turning it on, the report sending button will appear.
• Mock location app: replaces the real location of the device and transmits incorrect coordinates.
• View attribute inspection (during debugging).
• Select app to be debugged (choosing certain app and performing debugging).
• Wait for debugger (is inactive by default, activates when the app is being  selected for the debugging).
• Verify apps via USB. Apps security check, which are installed with the help of ADB/ADT. it displays inactive by default.
• Buffer size for logging (choosing the buffer log size, in which debugging log will be written down, 0-16 MB).

Networks

List of functions for setting the parameters of the wire and wireless connections:

• Authorize wireless display devices: screen parameters, which are connected to the device.
• Wi-Fi verbose logging: extended possibilities tracking connections and detailed log records.
• Aggressive Wi-Fi/cell handover: automatic switch to cell network during the weak Wi-Fi signal.
• Allow Wi-Fi roaming scans: activating Wi-Fi search depending on traffic size.
• Keep Mobile data turned on: using mobile data even while active using Wi-Fi.
• USB configuration. Also appears in the upper menu of the device when the device is connected to the PC. Used parameters are the following:
  • charging the phone;
  • MTP (transferring multimedia files of all types);
  • PTP (transferring only images);
  • RNDIS (smartphone functioning as a modem for PC);
  • audiosource and MIDI (sound synthesizer).
• Disable the absolute volume: used during issues on Bluetooth-devices, for example, wireless headphones sound very loudly or quietly.

Input

Parameters that control sensor tap display:

• Show touches: tap place will be displayed on the screen.
• Show pointer location. All gestures and taps will be displayed on the screen with dotted lines.

Drawing

Set of functions which are responsible for the  interface:

• Show screen updates: highlighting the windows during update (shimmering).
• Show layout boundaries: it can be useful if it’s necessary to check the accordance of the tap on the element.
• Force RTL layout: fully mirror the interface to the other side.
• Window animation scale:  the speed of the animation effects in the app windows.
• Transition animation scale: windows or apps transition speed.
• Animator duration scale: changing the displaying time of animation effects or their turning off. Helps to speed up or down OS visual work.
• Simulate secondary displays: creating a duplicate of the main screen, that allows testers to simulate different sizes and resolutions.
• Minimum width: using for managing the size of interface elements. This function is available for OS v7 and higher, but isn’t present  in  all smartphone models.

Flexible graphical settings are the prerogative of the newer models of the Android devices. Even emulation of the additional visual effects may be set for user needs.

Hardware-accelerated rendering

Settings and functions set that  improves device components work efficiency:

• Force GPU rendering: activation of permanent work of graphical processor for 2D graphics rendering. This function can either speed up or slow down the smartphone performance.
• Show GPU view updates: those screen parts which are involved in the GPU work process at the moment, are highlighted by shimmering.
• Show hardware layers updates: Turning on this function allows to highlight updated elements with green light.
• Debug GPU overdraw: highlighting the areas where graphical interface elements are overlaid. 
• Show non-rectangular clips: complex shape graphical elements are highlighted.
• Turn on 4x MSAA: forcing the smoothing mode turning on. The more smoothing, the better images look, but the device performance is quickly decreasing.
• Turn off hardware overlays: GPU is always used for screen composing and elements layout.
• Simulate color space: changing the device color rendering. It’s mostly needed for people who have color diseases. Monochrome mode can be used in reading mode for battery saving.

The loading testing and product optimisation testing are mostly used by  the third-party software via USB-connect with PC.

But it is essential to remember that built-in tools also can be used for this purpose. And often they even provide the more in-depth character data.

Monitoring

• Strict mode: finding complex resource-intensive operations during execution of which the screen starts to shimmer.
• Show the CPU usage: the color diagram is displayed on the screen, which demonstrates real-time CPU or  the GPU usage level.
• GPU rendering profile: activating the mode of GPU work time logging.

Memory allocation is sometimes an important part of product testing for SD-card or device storage settings.

Apps

App interaction settings section:

• Do not keep activities: all data about app operations are deleted after its closing.
• Limit background processes: limit the amount of simultaneously working background processes. If you know directly which processes aren’t necessarily for the permanent use, then this function allows to highly improve system productivity and decrease battery usage.
• Show all ANRs: this function turns on the display of the notifications  about inactive or not correctly working apps, even if they are in the minimized mode or used in background.
• Inactive apps: the app list  where the app statuses can be changed to active/inactive,is displayed. 
• Force allow apps on external: turning on the option of the  installing apps on the SD-card, even if the apps don’t support this function.
• Force activities to be resizable: forcing the app window to resize, even if the app doesn't support those.
• Reset the ShorcutManager API call limit: function allows to reset all the app shortcuts.

While working with any Android device it is always important to understand how and where certain settings are placed. Whether it's a switcher of taps displaying (touching the screen), or USB debugging. The time that could be spent researching the app functionality, is spent on searching for some function.