App: Tuner - gStrings

Creator: cohortor.org
Type: Tools
Description: Ad supported tuner for any musical instrument (violin, guitar, bass, piano etc.). It can come in handy if you are musician.
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App: Speedtest.net Mobile

Creator: Ookla
Type: Tools
Description: The most simplest and fastest speed testing tool to use. Choose between given servers to test your download and upload speed. Keeps data of your previous testings so you can keep track of it.
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App: Tiny Compass

Creator: Nikolay Ananiev
Type: Tools
Description: Nothing much to say here, simple and useful compass app. 
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App: Vibration Meter

Creator: Smart Tools co.
Type: Tools
Description: This cool app transforms your phone into seismograph. Measures your phone's vibrations and sorts them into 10 groups (from vibration felt only by animals to total destruction). Uses MMI scale (Modified Mercalli Intensity).
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App: Smart Measure

Creator: Smart Tools co.
Type: Tools
Description:  Cool app for measuring height, width or distance of any object using trigonometry.
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App: Sound Meter

Creator: Smart Tools co.
Type: Tools
Description: This app uses your phone's microphone to measure noise level in decibels . First picture shows diffidence in readings between several devices and second one is actual UI.
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App: Fast App lock

Creator: George Android
Type: Tools
Description: Select apps you want to secure, put widget on desktop and with one tap lock them all. Unlock by drawing a pattern or input regular password.
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