Simple Battery Monitor shows time remaining, charge percentage, and battery status in a compact menu-bar app.
It warns you with an orange-arrow icon when some apps consume too much power
Time remaining is based on your most current consumption, so it gives you an accurate estimate of how long your demanding app will last till the battery is empty
Time remaining is for both charging and discharging
You can view cycle count in status menu
You can quickly access Activity Monitor to see per-app power consumption, and System Preferences to change Energy Saver preferences
You can set the app to launch automatically at login