Publisheet - Publish your Excel sheets to the web as dynamic web applications with formula support.
Fuse - Fuse is a UX tool suite for mobile app designers and developers.
CALCONIC_ - Build & add interactive calculators to your website! Choose from more than 50 premade calculators or build your own from scratch. No coding required. Free plan available. Zapier Integration. Publish Anywhere.
Siberian CMS - Siberian is an Open-Source and Free App Maker. Unlimited Push Notifications. Unlimited features. Fully Customizable. Download it and build your own app now!
SpreadsheetConverter.com - Use online spreadsheets, smart forms and beautiful charts in your blog or website. Put your booking and order forms online. Show live charts. Change any cell and the online spreadsheet or live chart immediately updates itself.
GoodBarber - GoodBarber is a mobile app creation platform.