AppMySite - An automated no-code app builder
Thunkable - Powerful but easy to use, drag-and-drop mobile app builder.
Cyclr - Powerful SaaS integration toolkit for SaaS developers - create, amplify, manage and publish native integrations from within your app with Cyclr's flexible Embedded iPaaS.
Xamarin.Android - Integrated environment for building not only native Android but iOS and Windows apps too.