Bandhelper is awesome. I've been using it forever (since it was Setlist Maker) and it does wonders for us.
BH was originally only for iOS and Android, but has now grown to support PC and Mac versions, as well as a website, so you can really access it on just about anything, and everyone can keep their stuff synced up however they want.
Since it's originally based off an app that was primarily designed for setlists, obviously that works super good and is very well fleshed out. It stores all of our songs, charts, lyrics, documents, even mp3 files to reference tracks.
It also has a calendar that ties into the sets you create, and has options to tie in things like finances and travel and stuff like that. I personally do not use these features, but I know they're there.
I am unsure of if it has any internal messaging capabilities. I do not think so - we just use group texts. Someone else mentioned Discord - I'm a huge fan of that if you don't like texting.
I do use its MIDI implementation pretty heavily though. It supports basic bluetooth page turners and stuff like that, but it also can be used to trigger other software, and also be triggered by external apps too. My bands run clicks and tracks through Ableton, which is super intensive and hairy to work with, but with BH, I can make a new setlist 5 minutes before the show, sync up everybody via wifi, and Ableton will follow the list in real time automatically. I can even call audibles and skip tracks and everything works.
The learning curve is a bit steep, and it is subscription based, so those are some downsides. Arlo, the owner/designer/programmer, is fantastic and is quite consistent and speedy with answering questions however.
Big ups to Bandhelper!