iOS Stack - A curated collection of iOS resources for app builders
Dashboard UI Kit - A modern & responsive dashboard UI kit for designers.
Lightwell - App creation platform for creatives.
Now UI Kit - A beautiful Bootstrap 4 UI kit. Yours free.
AppToolkit - AppToolkit provides tools to build iOS screenshots, app landing pages, and to monitor app reviews
Bots UI Kit - Fully customizable Sketch UI Kit for Messenger Platform