Airtable - Airtable works like a spreadsheet but gives you the power of a database to organize anything. Sign up for free.
Headspin - Test your mobile app on different global cell networks
FriendlyData - Communicate with databases like a human
iotlist - Discover the internet of things
SpreadsheetDB - A database that you can query with spreadsheets
Particle Electron - Cellular IoT development board with a simple data plan