I wanted to build a clock that would inform me of different bands of time without displaying the actual time.
This is because I sometimes wake up in the middle of the night. I think it's acceptable to get out of bed before one's alarm, but there is a certain hour that the only reasonable option is to try to fall back asleep. For me, right now, I have an alarm at 7am, but I think it would be unreasonable to get out of bed before 5am. Currently, I check my iPhone display for the time. I've been informed by sleep experts (people who took `PSYC 135: Dement's Sleep and Dreams`) that this diminishes the chance I'll fall back asleep. Given how unsuccessful I am at falling back asleep when I do wake up in the middle of the night, I'm willing to try something new. However, I'm not willing to try their recommendation of just lying in bed without checking anything until my alarm goes off at 7am. This is because 7am is the outside range of when I think is acceptable to wake up. I don't want to enforce that I stay in bed until then. At one phase of my life, I strictly got out of bed at the same time every day. In theory it is better sleep hygeine, but I found it too rigid and inflexible for shifting demands with work and life, and it slows recovery if you need extra sleep one day due to preceding poor sleep or accrued sleep debt or some other reason. Therefore, I've landed on setting up a minimal "display" that tells me (unprompted, so only relevant if I wake up on my own) when it's acceptable to wake up. My iPhone's alarm will continue to enforce my later bound of when I must reasonable wake up on days that I feel I need to enforce a minimal wake up time.