My first mobile app, developed and released in 2013 for the launch of the BlackBerry Z10 running BlackBerry 10 OS.
App design
For this app, the user sets two components of the exposure triangle: exposure time, aperture, and ISO. The app then suggests the third component for a properly exposed scene.
The maths implemented in JavaScript follow the incident light exposure equations.
Like a dedicated light meter, the app measures the ambient light falling on the subject. Measurements are taken using the integrated ambient light sensor. Calibration was checked on several BlackBerry devices against a dedicated light meter.
The exposure recommended by LightGuru could then be used by the photographer to set a fully manual vintage camera.
Tech stack
The BB10 app was developed using the Cascade UI framework. It provided building blocks for creating apps quickly, as well as APIs for accessing device peripherals and components such as the light sensor and camera.
- The front end was built with QML and JavaScript.
- The application logic was written in Qt/C++.
In 2026, BlackBerry devices and BB10 are obsolete. For reference, here is some useful information about Qt development for BlackBerry.
License
Open source, GPL-3.0 Published on Github.