When comparing GroupMe vs Hall, the Slant community recommends GroupMe for most people. In the question“What is the best team chat software?” GroupMe is ranked 49th while Hall is ranked 60th. The most important reason people chose GroupMe is:
GroupMe has a built in function to read receipts.
Specs
Ranked in these QuestionsQuestion Ranking
Pros

Pro Reads receipts
GroupMe has a built in function to read receipts.

Pro Great web client
GroupMe has an excellent web client that can be used to send and receive messages and manage groups from the desktop.

Pro IFTTT Integration
Allows sending messages from web services via IFTTT.

Pro Integrated calendar
It's possible to add location and time with reminders directly in the GroupMe app.

Pro Makes it easy to silence 1 or all groups
GroupMe has settings that allow muting a single group or turn off all GroupMe notifications from within the app.

Pro Does not require everyone in the group to have a smartphone
GroupMe can set up a custom phone number which allows people without the App to send and receive messages. This makes it easy to add anyone to messaging.
Pro Cross-platform desktop, mobile and web
There is iOS, Android, Mac, Windows, Linux and web software available.
Pro Multiple service integrations
Hall integrates with Dropbox, Box, Asana, Trello, Github, Heroku, Jenkins, New Relic, Pivotal Tracker, UserVoice and Zendesk.
Pro Free
Free on on all devices.
Pro Dropbox and Box integration
You can use Dropbox and Box to share files in Hall.
Cons
Con Drains battery fast
GroupMe, in order to have a constant connection which allows for notifications drains the battery of a device quickly, which is not ideal for a messaging app that one needs on time notifications from.
Con Has gone out of service
But may be integrated into Atlassian's HipChat.
