Day Counting Devices and Tech Tools

I track time using day counters on my phone—both the days passed and those left, like how long it’s been since I last unlocked or had an orgasm, plus when I might get released next. My KH sets five different counters with unique background images for each one. It brings a bit more mystery to our chastity dynamic; seeing the numbers climb or drop is always satisfying. After all, as they say, a picture speaks a thousand words.

Does anyone else use tech in their chastity routine? If so, what tools do you rely on?