Mightytext - Send & Receive SMS Text Messages from your computer. Sync'd with your Android #
AV-TEST - Independient IT-Security Institute
Zeplin - Collaboration app for UI designers & frontend developers
Diffen - Compare anything to find similarities and differences. Read, improve or create comparisons.
ActiveWords - Auto correct on steroids
AwesomeSearch - A search engine aggregating multiple Awesome-lists, which are curated lists of software related projects, mostly on Github.