Apple Warranty – Will Apple Service Secondhand iPad Still Under Warranty?

No, you can get an app like NetStat and see the ports that open when WiFi is connected as well as when data is available, but not connected.

The carriers would know where it was since their cell towers would have a fix on the IMEI (or equivalent for non GSM carriers) - but that database isn't integrated into the Find My Phone service in any way we can see.

You are correct that the hardware talks with base stations that are near by and it would be nice (kind of like 911 service is permitted even when a line is inactive) for consumers to have this work without respect to billing status.

The short answer would be no. A 5 y.o. battery won't last as long as a new(er) one. However, depending on if the original owner followed Apple's care instructions, and it doesn't have a high cycle count, it may not be much lower.

A lot of it depends on the care the battery was given. If the battery has just been sitting in a box this whole time, it's performance may be lower. Batteries need their "juices" (electrons) flowing in order for them to stay healthy.

On the other hand you have cycle count. A battery only can handle so many cycles before it wears out. Simply put, the higher the cycle count, the lower the performance.

Apple recommends storing a battery at 50% for extended periods of time. If it's fully charged or discharged when stored, this will again affect battery life.

Here is a comprehensive guide to Apple notebook batteries.

Of course, all this doesn't count any engineering changes that may have been made for the better in newer batteries.