Besides ease of use and the practicality of having it at hand at all times, these apps show you important stats like longest time between periods, average time between periods, current time since last period. Same with length of period. All useful stats for you, your doctor, and potentially your partner if you’re trying for a baby.

It’s not co op but head to head. But if you haven’t played duck game, I feel like you are missing out on some of the best local multiplayer pc has to offer.

If that’s too competitive, try Ultimate Chicken Horse - if you want some incentive watch a guy named Northernlion play it on YouTube

Next on the semi co op is Crawl although it’s still a little competitive, I can’t do it justice by describing it but it’s great, videos will do better to describe it.

If co-op is a must, I second divinity.