CellDaddy wrote:Thanks for everyone's help - I appreciate it.
To summarize what I've learned from this and other discussions on the web:
- There's no hard and fast rule that determines which network Android uses for data - it depends on the individual circumstances of a situation and the particular phone.
- Generally, Android will choose WiFi if a WiFi network is available and the signal strength is sufficiently strong. This matches my personal experience over several months as measured with the My Data Manager app: I mostly use my phone at home and at work, where there are strong and consistent WiFi networks; My Data Manager reports that most of my data has been transmitted over WiFi.
- There are some apps that will only operate over the cellular data network. AT&T's Address Book is one such app (which is why I sync my contacts with Google and not the Address Book.)
- Some phones will choose the fastest available network, which may well be the 4G LTE network. I don't know if Moto X does this. I suppose I could ask Motorola.
Thanks for the tip about turning off WiFi when I'm in an area where there are unlikely to be open WiFi networks, like when I'm on an extended drive through the countryside.
to expand - it is not only user written apps it can be processes of the phone's OS, the cellular data type used is dependant on multiple factors, signal strength being the primary determination