When comparing IMO vs Ryver, the Slant community recommends IMO for most people. In the question“What is the best team chat software?” IMO is ranked 14th while Ryver is ranked 20th.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Video call support
Pro Beautiful User Interface
Although IMO has a comparable, and in some cases superior, feature set when compared to the competition its key selling point is its interface.
From LifeHacker when it won "Best IM Client":
Signing on, navigating chats by tapping the tabs at the bottom, searching for buddies, and virtually any other operation is easy to find and use. The app, itself, is very quick. Even sending a voice IM, if you don't feel like typing, is responsive and sends quickly. Everything imo does it does well, but it's excellent navigation really makes it top notch.
IMO also has a fully functional website that you can use for chat while on your desktop or laptop. This really puts IMO ahead of the competition as you can use the same system on all your devices so you don't have to deal with overlapping notifications etc. (Note: IM+ also has this feature)
It should also be noted that it has the highest rating in the App Store due to both the UI and its stability.
Pro Easy to switch between conversations with tabs
Tabbed chats make it easy to switch between conversations
Pro Lists and chat histories are searchable
Both your buddy lists and chat histories are searchable.
Pro Accounts can be linked so you don't have to sign in to several accounts
Pro Push notifications
Pro Concurrent sessions
Concurrent sessions allow you to be logged in on your desktop while also being logged in on your phone.
Pro Chat groups
Pro Free
Pro Threaded conversations
Ryver has Facebook like "Posts" that allow for threaded conversations to occur among teams.
Pro Unlimited users
There is no limit to the amount of users you can invite to join your instance/account of Ryver.
Pro Upvote and Downvote
"Do you like this?" questions can easily be answered with up or down votes.
Pro Drag and drop file sharing
Start a new post, drag your file (photo, doc, pdf, etc. 100MB limit), and starting discussing.
Pro Fast
The app loads fast on start-up. Any new chats, comments, and posts show up instantly. Overall, the app just feels rather speedy.
Pro @mentions for users and teams
Get someone's attention with @mentions.
Pro Desktop and mobile apps
Apps work great on Mac, Windows, iOS, and Android.
Pro Free conference calling
Pro Can hide topics until new comment is received
You can remove a topic from your nav bar and have it reappear when new messages are sent in that topic.
Pro Hosted on Amazon
Hosted on Amazon cloud. Service is very reliable. Ryver has been unavailable maybe once or twice in the 6 month period.
Pro You can edit a chat message
With Ryver, you can edit chats that you've sent.
Cons
Con No support for third-party instant messaging networks
On March 3, 2014, IMO will start discontinuing support for all third-party instant messaging networks.
Con Having Chat and Posts for Teams is confusing to some users
It takes some time to get accustomed to all the features of the program, like a separate chat and a feed for team posts.