Plenty of new DSLR and mirrorless cameras come with WiFi & Bluetooth connectivity and convenient remote control features. Even if you have an older camera, you can use these wireless transmitters and controllers to interact with it from your smartphone:
Travelite TL102 WiFi Dongle: lets you use your iOS or Android device as the viewfinder of your camera. It supports Sony a7RII, a7R, a6500, and other popular Sony cameras.
CamFi: allows you to remote control your camera and use your tablet as its viewfinder. Supports various Nikon and Canon cameras. The battery life lasts up to 6 hours.
CamRanger: a wireless transmitter for Canon and Nikon cameras. It gives you live view, control over shutter speed, aperture, white balance, iSO, and more.
SlingStudio CameraLink: combines with Sling Studio to let you send video from your camera or camcorder without a HDMI connection. It supports resolution up to 1080p.
Have you found better iOS compatible wireless camera controllers? Please share them here.