GroupMe is a Microsoft app made for collection and sorting contacts and friends into easy-to-manage, well, groups. Contacts can be added to the app by their phone number or email address and a variety of chat options are available. The new poll feature works as an attachment to chat messages.
People often criticise Microsoft for supporting other app ecosystems over Windows phone but GroupMe is a good example of one of their own apps that they update on Windows phone as often as iOS and Android. GroupMe support is also built directly into the People app on Windows 10 Mobile (in the Groups tab).
Do you use GroupMe? Let us know why or why not in the comments below.