Apps like Concentration Tool

Here are some great alternatives to Concentration Tool by gustar-droid :
Concentration training
Concentration training
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White Noise - calm,concentrate
White Noise - calm,concentrate
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FocusTimer /Pomodoro Technique
FocusTimer /Pomodoro Technique
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Speed reading - Schulte table
Speed reading - Schulte table
★4.3
Nature sounds relax & sleep
Nature sounds relax & sleep
★4.7
Piano Relax Music
Piano Relax Music
★3.6
Pomodoro Timer - Focus Keeper
Pomodoro Timer - Focus Keeper
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Decoder Brain Training
Decoder Brain Training
★4.1
minimalist phone: Screen Time
minimalist phone: Screen Time
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Screen Color Filter Lite
Screen Color Filter Lite
★3.9
OffScreen - Less Screen Time
OffScreen - Less Screen Time
★3.3
Focus Hero: Achieve your Goals
Focus Hero: Achieve your Goals
★4.1
Foca: Pomodoro Focus Timer
Foca: Pomodoro Focus Timer
★4.4
Brain Wave Tuner Advance
Brain Wave Tuner Advance
★3.5
Color Filter
Color Filter
★3.5
Screen & Notifications Dimmer
Screen & Notifications Dimmer
★4.5