Theia's lens calculators (more accurately image resolution calculators) let you see what to expect from different lens-camera combinations. The pictures represent the field of view for a given camera-lens combination and the image resolution. You can use these pictures to set expectations for your customer about how far away a license plate can be read or what level of detail can be seen in a person's face.
Theia offers smart phone app versions as well as a free online version (see below). For the mobile app, the picture represents the image resolution you can expect from the camera and lens combination.
Android

The lens calculator app is currently available for Android. It can be found by searching for "Theia" in the Android market place on your Android phone.

iPhone

The lens calculator app for iPhone/ iTouch is now available. Search for Theia in iTunes and download the app to your mobile phone.