I'm sorry if the response was a bit "terse". In my experience, this is one of the most frequently asked questions. There are some internet "standards" that affect the way devices choose which WiFi access point to use. i.e. there is some negotiation between the device and the AP over what each of them is capable of doing, such "can you do 802.11n?" "No, only 802.11b." etc.
Once connected, some devices seem reluctant to drop the connection in favor of another AP. So, one technique that some peope have tried is to power off the device and then turn it back on. Since the router WiFi signal "comes up" while the satellites are still making connections to the router, some devices "see" the router first and get connected. Then, they seem to stick. Some people have reported success with the power off, then on technique. (Of course, this all goes to hell if there is a total power outage. Everybody gets power restored at the same time and they're busy connecting before the satellites are ready.)
