Restful API service

I’m looking to make a service which I can use to make calls to a web-based REST API.

Basically I want to start a service on app init then I want to be able to ask that service to request a url and …

How do you define a good or bad API?

Background:

I am taking a class at my university called “Software Constraints”. In the first lectures we were learning how to build good APIs.

A good example we got of a really bad API function is …

Using Retrofit in Android

I have an android app that has 3 activities :
A login activity
A tasks acivity where all tasks pertaining to a user are displayed (Populated using an Array Adapter)
A task_details activity which …