Pebble put out a "Timeline Challenge" when introducing their new Timeline interface, and Battery+ was the first app to claim the award.
Efficient and Power Saving Design
Battery+ runs in the background, but it is extremely efficient, and only wakes up the processor on occasion.
Battery+ pushes pins to your timeline whenever your battery starts to get low, giving you a little extra reminder in addition to its built in ones.
Customizable Battery Alerts
Battery+ knows when your watch will die, so just tell it how long before then you want to be reminded. Hold "Select" to open the menu.
The dashboard view contains the most used information, such as the current battery percentage, time remaining, and run time. Cycle through stats with the "select" button.
The percent view shows a graph of your battery percentage over time. Click the "Select" button to cycle through different zoom levels.
The charges graph represents each charge cycle as a vertical bar. The blue is the maximum time you could have gone without charging, and the green is that cycle's actual run time.
The record view shows your best ever run time without charging or turning off your watch! It also shows how close you are to beating your record.
Silent Background Tracker
There is no need for Battery+ to be open, as it tracks the battery silently in the background. It only opens occasionally to push pins to your Timeline.