Leaf Spy Good and Leaf Spy Bad...
There are two meanings to Leaf Spy, one very good, and the other, in my opinion, not so good.
First te good Leaf Spy:
Some bright guy in the UK developed a smart phone app originally called
Leaf Battery App then it was renamed Leaf Spy, with a free lite version (Leaf Spy Lite) and a pay version (Leaf Spy Pro). The name changes may have continued to evolve, it's hard to keep track.
I have the free Leaf Spy Lite, and I think that it is unquestionably amazing. I have an Android phone, it is also available for iPhone. The app requires that you buy a Bluetooth enabled OBDII dongle, which are available on ebay. Apparently the app requires the full implementation of th Bluetooth protocol in the OBDII connector dongle. The first dongle I got (cheapest, at $4US) didn't even connect. Most likely this was because it did not have the full implementation of the Bluetooth protocol. I ordered another (about $11US) that did have the full protocol, and it connected with no problem to the app installed on my Android phone.
When everything is working correctly, this is what you get:
The information it yields is simply amazing.
Also, here is a youtube video of a guy who explains pretty well what is going on:
I can't imagine not having this if you have a Leaf.
Even more important, if you are considering buying a used Leaf, this will give you valuable information about your battery that you can not get any other way.
Best,
-AC_Hacker