You'll probably want to use a combination of GA / Mixpanel and a heat mapping tool like Crazy Egg for a low budget combination that will give you good data.
https://amplitude.com/. Amplitude is probably one of the best out there for web/mobile analytics to get started with. Very generous free plan.
Alternatively for a more automated solution (though not completely automated) https://heapanalytics.com/
Mixpanel is also a solid choice, but more expensive and doesn't give as much flexibility in the queries with user profile filters.
Keep in mind Mixpanel/Amplitude require some coding to send your tracked events, Google Analytics will give you a lot for free and minimal coding by simply dropping in the SDK.
When combining a series of tools together try https://segment.com/. You can pipe the events into any system from there without having to spend additional time doing data engineering. For example, you can use Segment to one click turn on a firehouse of your events stream into Intercom, or another marketing automation tool like Hubspot, Marketo, Pardot, etc.
If you have a mobile app, Flurry is free and quite good also.