One of my use cases is to monitor my surveillance cameras, which drains my batteries quickly, but I have unused wemo switches that I could put on a schedule to just cycle power more frequently for intermittent charging.
The timer switch I grabbed to do my proof of concept only has 15min resolution (it's a weird old mechanical one where you move plastic pins in the stop/start time rings). I recall setting it to 45mins because the docs says the iPad gets 80% charge in 1 hour, and it'd occasionally run down and switch off, so I bumped it up to 1hr and haven't touched it since.
I just checked now, it charged for an hour overnight finishing ~10.5 hours ago, and is currently saying 59% charge. I honestly have no idea how low or high the charge level gets, just that I haven't needed to wake it back up from a shutdown in over 4 years...
I've come to doubt the details there are important. Don't leave it on charge 24x7, that'll kill it fairly quickly (~9 months in one data point of mine). Charge it long enough and regularly enough to keep it running, but at the low end of that spectrum. Keep in mind my goal here is less "extend the life of the battery", and more " prevent the battery from swelling up and damaging the device/catching fire", but I suspect there's a fair bit of crossover between those goals, since I've not needed to increase the charge time in response to any battery capacity decrease over 5 years (which in retrospect surprises me somewhat).
If I was aiming to maintain the best possible range in an electric vehicle, I'd probably pay much more attention to max charge and min discharge levels, but "the simplest possible thing" has been working well enough for me to just leave it alone.
If it dies on me tomorrow, I'll be happy enough with the use I got out of it and the tradeoff of time I spent futzing with it.
(Note: I'm also quite familiar with abusing LiPo batteries way past safe limits, I raced FPV quadcopters 5-6 years back, and in my worst excesses, I'd be aiming to completely drain a flight pack in ~2 minutes. They'd end up too hot to touch, and start to decline to the point of not being race competitive within 20 or 25 cycles. They'd also catch into unextinguishable fire in big crashes and occasionally while charging. I have a healthy fear/respect of high capacity and high current LiPo batteries...)
Made that mistake myself. I now have a wall mounted iPad with the charger plugged into a timer powerpoint that only switches on for 1hr a day. Been running like that for 5+ years now without issue. (I'd planned for that to just be a proof of concept, and to use a wifi powerpoint that'd turn on when the battery dropped to 20% and back off where it hit 80%. The easy solution has turned out to be "good enough" and has remained in production, like that cronjob perl script from 2004...)