There are many similar apps in the Google Play Store. I just happened to try out the one that is called "Passport Photo Editor", developed by Dak Bhavan (in case you are interested to give it a try).
The app allows you to pick the dimensions as required for any number of countries. The huge list provided probably covers any country you want. Using it is a breeze. All you need is to find a background that meets the background colour required of the passport photo.
The example below was a selfie that I took against a plain coloured wall, in ordinary ambient light. It took less than a minute to create the 6-photo jpeg image; at no less than my very first try.
I took it to Harvey Norman this afternoon. I transferred the image from my smartphone to the kiosk, paid 20 cents for the print, and voila! The size of the passport photo came out exactly 35mm x 45mm, and the size of the face exactly meets the requirements for an Australian passport photo. By the way, it costs AUD$16.95 to have this done at a post office, so it is definitely worth trying out.