Can I combine lines and points in one survey?
maybe in a clever way, like reffering to another survey for a dieferent geometry type,
or using start point of line to make apoint out of it?
No 123 forms dump data into Feature classes and a Feature class cannot be two different geometries at once.
You can make a repeat and add a line or point question to it. So the parent has one of them and the repeat the other.
Or what we do is have two geopoint questions, one for the start of the line and one for the end. Use pulldata to grab the x and y into fields. Set the end of the line geopoint bind esri type column to null so that it does not try and add it to the service.
Hope that helps.