There are plenty of awesome iOS astronomy apps that can teach you a thing or two about our solar system and space and help you find your favorite celestial objects in the sky. AstroAid is also worth a look. It is an amateur astronomy app that visualizes what you will see through your telescope.
The app takes into account magnification, actual field of view, visual magnitude limit, and other parameters for your telescope/imager. It has Messier, NGC, IC, and several other object catalogues. While the app has plenty of camera lenses, imagers, and optical aids included, you can always add your own custom entries.
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