Why must you do this?
Because the app works in the background silently, you must configure the essential settings. If not, it will stop working suddenly or do not work properly. For example, with the saving mode, if the battery - is turned on, the app will stop saving the battery, and then you will not see the data of the target device.
That is why almost people complained that the app work 2 or 3 days after installing and stop working suddenly and after that it works again. It is because they did not do configurations as guides.
How to know the Android version number?
It is effortless to know the brand/manufacture - it appears on the face or the back of your device/phone.
About the Android version, normally you can go to Settings, About Phone; or Settings -> More Settings -> About Phone; or Settings -> Additional Settings-About Phone, you will see number Android version label with numbers such as 8.1.0 or 7.1.7 or something like that.