The best alternatives to GluePrint are Cleanmock, Mokup Frames, and Apimint. If these 3 options don't work for you, we've listed a few more alternatives below.
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AssemblyAI— Speech-to-Text API with superhuman accuracy
Hamok is the easiest way to create beautiful mockups by providing a URL or an image and selecting a template. Responsive websites will automatically scale to the template. You can present a website in-app or export the mockup to an image.