I recently read that the battery tends to decline in capacity in relation to the temperature at which it is located.
The temperature of the battery increases and decreases depending on our use, ie use the smartphone more and more the temperature increases, the less we use it, and more down, normally.
Is there an app that notifies you that the battery temperature has reached a level harmful? but without this app remains fixed in the status bar, but that only appears at a certain level of the battery.
I apologize for my English, but use google translate because I do not speak English well = (