Open source (GPL), no cost, no ads, small app size
Saves to Google Drive, local storage or HTTP(S) POST
No user information is sent to anyone (except saving the photos to the user-specified locations).
Can be used as a primitive security camera
Can be pointed at plants to watch them grow
Can be used to monitor pets while away
Can be pointed at birds' nests to watch their activity
Can be used to capture sunrises/sunsets
Can be installed on multiple Android devices to capture several camera angles
Can be pointed at a porch to check if packages have arrived
Can be installed in a garage to show if a garage door is open
Can be pointed at a thermostat/thermometer/display to monitor temperature/humidity/etc
Timelapse Camera lets you use an old Android phone or tablet as a networked timelapse camera. It can use the front, rear, or both cameras with specified resolutions. It can upload photos to Google Drive or via HTTP(S) POST. It can also save the photos to local storage. You can have it take a photo every minute, every hour, every day, etc.
As most Android devices have a camera, battery and wifi hardware, it does not need any wires to act as a timelapse camera. Depending on your device and time delay between shots, it could potentially run for several weeks without charging.
If you have it save to Google Drive, you can view the saved photos with any other compatible device. Potentially, you could view the photos from the other side of the planet in almost-real-time.
As an option, it can delete old photos from Google Drive. You can select how many old photos to keep and any more than that will be deleted.
There are many options to reduce power use. Wifi can be toggled automatically and the screen can be turned off on newer versions of Android. These don't matter if you can leave power attached.
The scheduling for the camera uses Android's internal "alarm" mechanism so the device can sleep between shots.
For full free source code, licensed with GPLv3, please visit the web page link.
If you're having trouble uninstalling, it's likely you authorized the app as an administrator. This status is necessary for turning off the screen to save power. Your device may require you to de-authorize the administrator status before allowing you to uninstall. You may find this in Settings->Security->Device Administrators.