How to Share One Phone Between Two Kids Fairly

One phone and two or more kids means someone's always waiting, and the block list, schedule, and everything else in a tool like CrenelView applies to whoever's holding the phone at that moment, not to a specific child.

Why does sharing one phone between siblings cause so much fighting?

Because there's no natural stopping point built into a turn the way there is with, say, a board game's set number of rounds. One child's turn tends to expand to fill whatever time nobody interrupts it, and the sibling waiting has no way to know if it's been three minutes or fifteen. Most of the fighting isn't really about the phone itself, it's about the uncertainty of not knowing when a turn will end.

Does CrenelView have separate settings for each child?

No, and this is worth knowing plainly rather than discovering it later. CrenelView has one block list and one schedule for the phone itself, not per person. Whoever is holding the phone gets whatever that phone's current settings allow, whether that's a five-year-old or a ten-year-old. If two children need genuinely different rules, that's a real limitation this specific tool doesn't solve.

How do I make turns feel fair without a stopwatch every time?

A visible, fixed length works better than judging by feel in the moment, since "a few more minutes" means something different to the parent holding the stopwatch than it does to the child watching the clock. A kitchen timer, a phone timer set by the parent, or a specific number of levels or episodes agreed on beforehand all give both kids the same visible countdown, rather than one child's turn quietly running long because nobody was tracking it closely.

What if one kid needs longer for something legitimate, like a homework app, than the other?

Separate the reason from the turn-taking system rather than trying to build one rule that covers everything. A homework app that's genuinely needed for schoolwork is a different category from entertainment turn-taking, and it's reasonable to treat it differently, used before or after the turn-taking rotation, rather than competing for the same block of time.

Does the "Allow for a while" timer help with turn-taking specifically?

It can, used as a shared visible countdown rather than a private one. Setting it for a fixed length, 15 or 30 minutes, and letting both kids see that the same clock applies to whoever's turn it currently is, at least removes the "how much longer" guessing game, even though it doesn't solve who goes first or track whose turn is next, since that part still has to be a household system, not a phone setting.

The phone can hold a length. It can't hold a turn order, that part still has to be a family rule you set once and stick to.