What’s the best free Android app for measuring reaction time?
Last week, I was on my bike and got hit by a car while distracted. I wasn’t badly hurt, and the bike is tentatively fixed, but I want to be sure I don’t crash again.
I figure sleep deprivation may have been a factor, even though I didn’t feel tired. I need a way to measure how alert/tired I am (MSLT and Eysenck aren’t options because I’m on Vyvanse), and was told reaction time would be the best metric.
Ideally I’d like it to output the harmonic mean after multiple trials, since  indicates that’s a better measure over a set of trials than the arithmetic mean. Standard deviation may also be useful given  (although the Vyvanse is for Asperger Syndrome and I probably don’t have ADHD). I’d also like to save results in a spreadsheet (either Google Docs or CSV export), in case I ever have other variables to correlate it with. A red/yellow/green assessment with respect to traffic safety would be nice too.
This bike crash is what’s bringing me into QS for the first time; I probably won’t have the time and money for really broad self-tracking until I finish grad school.
 M. Basner and D. F. Dinges, “Maximizing sensitivity of the psychomotor vigilance test (PVT) to sleep loss.,” Sleep, vol. 34, no. 5, pp. 581–91, May 2011.
 C. Fassbender, H. Zhang, W. M. Buzy, C. R. Cortes, D. Mizuiri, L. Beckett, and J. B. Schweitzer, “A lack of default network suppression is linked to increased distractibility in ADHD.” Brain research, vol. 1273, pp. 114–28, Jun. 2009.