Are you Nexus 5 users?
Many Nexus 5 clients have complained on Google support forums about the battery problem (battery drain) when using apps (for ex: Skype) with cameras.
Some clients reported that the smartphone also heats up.(發熱)
A Google confirmed this bug and it will be fixed at the next software update.
This bug is found at the mm-qcamera-daemon apps by Google.
A Samsung Developers account;
Java Runtime Environment (JRE) including Java Web Start;
Internet connection with access to port 2600;