IMO vs AstraChat

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.

Tabbed chats make it easy to switch between conversations

Both your buddy lists and chat histories are searchable.

Concurrent sessions allow you to be logged in on your desktop while also being logged in on your phone.

Messages are received from clients using secured (TLS or SSL) XMPP (jabber) protocol.

AstraChat is tuned to make very efficient use of the network connection and processor so you can be confident that it will use very little of your battery or data allowance.

• RFC-3920:Core
• RFC-3921:Instant Messaging and Presence
• XEP-0012 Last Activity
• XEP-0016 Privact lists
• XEP-0054 VCARD-temp
• XEP-0085 Chat State Notifications
• XEP-0153 vCard-Based Avatars
• XEP-0172 User Nickname
• XEP-0184 Message delivery receipts
• XEP-0191 Blocking commands
• XEP-0198 Stream Management
• XEP-0199 XMPP Ping
• XEP-0176: Jingle ICE-UDP
• XEP-0136: Message Archiving
• XEP-0045: Multi-User Chat