Hi Dan - I just tested the map service in a new map, and I am able to expand the service to see the sublayers. Looks like I will need to figure out the issue between the web map and Collector. It is a map service from Server, version 10.4.1.
I am having the same issue. If I open a brand new map the layers will expand, but after I add about 8 more layers it stops expanding. After I removed all the layers, it expanded again. Using a map service from Server, version 10.4.1 and Android 6.0.1
Still experiencing the same issue as M Torres. If I keep my service layers under 7, then the map service sublayers appear. If I have more than 7, Android devices lose the ability to expand. Not very useful for our staff that needs to collect a large amount of data on many of their surveys. Are we expected to just provide them with surveys that they have to switch between if they are using an Android so they can utilize all of the necessary feature services? Any chance there is a remedy for this issue in Android? Many of my users are moving away from iPhone (kinda trending that way).
Specs. Services from Server 10.4, Collector v 18.0.1, Android v7. Occurring on Samsung Galaxy 7s's and Samsung Galaxy Tabs S2. Everything is just fine in iPhone, but you shouldn't need to have an iPhone to utilize all of Collector's features.