Apple has a great video series called How to Shoot on iPhone. They share some tips and techniques to help you take better photos, and enjoy them, with your iPhone. Here is a guide on how to shoot a horizon.
Steps for how to Shoot a Horizon on iPhone
- Turn on Grid in Settings
Open Settings, then tap on Camera and slide the Grid switch to On.
- Turn on HDR for better highlights & shadows
Tap the HDR icon in the camera app (if your have auto HDR turned on in Settings > Camera you can skip this step).
- Frame the horizon along the grid lines
The horizon line should be level with a grid line.
Take your photo of an awesome horizon.