A free app for Android, by Angelo De Falco Alfano.

Calculation Transformers is an application to calculate the ratio of turns for autotransformers.

The app makes use of two methods to calculate the ratio:The first method is based on the power rating of the transformer. 

The second method is based on the size of the spool.

In both methods, the app provides the user with the ratio of turns and the type of wire and plate to be used in the construction of the autotransformer.

In addition, it provides information about the voltage and current that can be delivered to the load.

The app can be used by professionals and designers to calculate the specifications of an autotransformer.