OT: tripmaster for Android

[fizeus]

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​Hi all,

in the next days I'll deal with my first regularity race.

The roadmap (still unknown) should be something basic so I just have to set time in min:sec from one checkpoint to the other.
There should be about 10 laps with 8/12 checks per lap.

Can anyone please suggest a good tripmaster for android smartphones?
It wolud a really useful to use headphone button to record the checkpoint-pass-time.

Hope someone can help