I don't own an android phone, so there may be some more I don't see, but heres my list:

Web & App activity (search activity on apps and in browsers)

Location History (Creates a private map of where you go with your signed-in devices)

Device Information (contacts, calendars, apps, and other device data)

Voice & Audio Activity (storing your voice and audio inputs to your account, for example, when you say "Ok Google" to do a voice search)

YouTube Search History (Store your YouTube searches)

YouTube Watch History

They all have an opt out toggle.

Even if I use and Android phone I don't use gmail (K9 instead) and don't login in Google (I search from the browser), YouTube and maps. Only in Play Store, that can't be helped. I opted out from every tracking they let me opt out from, ads, location, etc.

That service confirmed that there is no data about me. I believe they know much more than that, but at least I'm making it a little more difficult for them.

Looking at mine I see:

* My Google searches, this includes audio searches and it let me play the audio.

* Watched Youtube videos

* Pages viewed on Chrome

I don't see any Android activity besides the google searches, could be because I'm using Sultan's CyanogenMod.