Federated apps are highly sought after on Cloudron, and the ones we have a MUCH appreciated. I installed Misskey and Calckey on my Yunohost instance, and set them up to use object storage. That was trial and error, but I got it working with iDrive's e2. I was curious how much data these would use compared to Mastodon.
After just over 1 month, MissKey has stored 92GB. CalcKey has stored 76GB. Each instance follows just three people (two of them are my Mastodon account and my Pixelfed account - both on Cloudron). Both have signed up to the same 4 relays. I haven't run any kind of "cleaner" to reduce the space (because e2 offers ALOT of space).
So, remembering how many of us were surprised with the storage needs of Mastodon when we were all first installing it, I thought I'd share these data points for anyone thinking of using these others services. I am glad I set up object storage immediately because the server running that YH instance only has 100 gb! I would absolutely hate trying to resuscitate a filled-to-the-brim YH instance.