Pipedream - Integration platform for developers
Thunkable - Powerful but easy to use, drag-and-drop mobile app builder.
Hoist - Hoist is how you integrate - Meet the microservices platform that talks to APIs
BuildFire - BuildFire is the easiest way for small businesses to build a mobile app in a matter of minutes for iOS and Android.
Zapier - Connect the apps you use everyday to automate your work and be more productive. 1000+ apps and easy integrations - get started in minutes.
MIT App Inventor - App Inventor is a cloud-based tool, which means you can create apps for phones or tablets right in your web browser.