I would like to recommend you an application with large number of downloaders. 20,000+ users downloaded Exposure Calculator latest version on 9Apps for free every week! Once you've used it, you'll be attracted. This hot app was released on 2019-08-12. More similar hot applications can be found here too.
Given an exposure (Aperture, Shutter speed, ISO), allows calculating equivalent exposures - set 2 new parameters (a combination of Aperture, Shutter and ISO) and the 3rd parameter is automatically calculated.
It is also possible to specify an ND filter of up to 30 stops, handy for those long exposure photographs to blur water and clouds.
The app also includes a timer for exposure of 4 seconds or longer.
Note: in the Shutter settings section there is a switch tor camera type (Canon/Nikon). This switch simply selects how a small set of shutter speeds around 1 second are displayed, choose the one your camera adheres to. Exposure calculations work for all camera makes, this switch is simply for display purposes.
Please contact me if you'd like to help having the app translated into your language.
Still worry about the size of the installation package? This top Photography app is just 0.9M. It means downloading this application consumes almost no traffic. 9Apps also provides other hot Photography apps(games) for android mobile phone. 9Apps provides massive new Apps and Games, free download and no need for root!