Retrosizer lets you compare the size of handheld devices and see how certain systems will appear on their screens. You can drag the devices and rotate them etc.
Add a device from from the panel on the right and see the controls in the bottom right to get started.
You can bookmark URLs to save and share collections and comparisons. Here are some links to get you started:
Contact: firstname.lastname@example.org | Development Roadmap 🡕 | Reddit 🡕
NB: Please note that Retrosizer does not (yet) function well on mobile devices.