The best alternatives to Mapchatter are Party with a Local, Mixvisor, and HeyLets. If these 3 options don't work for you, we've listed a few more alternatives below.
What do you think of Mapchatter?
Tanka— Tanka = Slack + Glean, built for fast-growing startups.
uLouder is a local platform which connects end-users instantly and automatically, by a self-determined (max 3.1 miles) geographical radius to seek information, publish stories or make announcements.