Battery level indicators: Do they consume more battery? I have a Samsung Galaxy Y phone, the battery level indicator that comes pre-installed in the status bar, shows only a graphical representation of the battery level and does not gives a number (percentage).

So, I have downloaded an app to indicate the battery level, but I am afraid that this would further consume more battery. I think so because, it shows up as "Ongoing" in the status bar:



I have tried many different battery indicators.
Yes, of course they consume battery. You can go and check in Settings >> Battery how much is the app actually consuming. (It should appear something like shown the following screenshot) I think it might not consume a significant amount like other apps, but just check it and see if you are okay with the amount of battery it is consuming.

Also, if all you want is remaining battery percentage, I would recommend installing a custom ROM like CyanogenMod that shows the percentage on the status bar itself. (See the status bar in the screenshot below)