Hi Mpho,
You can check the minimum device requirements for Catalyst here.
We no longer list the available/compatible tested devices from other vendors (there are too many devices in the world for us to effectively test them all and provide a thorough recommendations).
Based on the specifications of the Galaxy A2 Core models SM-A260 (here), I would expect Catalyst to operate on this device. The best thing you can do is 1) download the TMM app to your device, and 2) sign in and run the TMM application and configure it to connect to Catalyst (even if you do not have a DA1 antenna handy). First of all, if you can see the app in the Play Store, that is the first step to confirm the that device meets the basic requirements. Secondly, Trimble Mobile Manager will perform some check sand will inform you if you device is known to be incompatible. Based on the specification I do not foresee an issue on the SM-A260.