I recommend that you work through this project in stages.
First, forget about bluetooth and app inventor, and write and Arduino program which does what you want it to do. Figure out the RTC and the motors. If the program requires user input, read that input from the serial monitor. It sounds like you might need to enter a date time for simulation of what you would get from the phone. It's not clear what you mean by "compare" this received data with the DS1302 time/date.
See Robin2's excellent tutorial on how to receive serial data. Serial Input Basics
Then, add the Bluetooth to replace the serial input from the monitor. I strongly recommend BT 2.0 with something line an HC05 module. If you use an HC05, then the change from Serial input to Bluetooth is trivial and straightforward. Bluetooth is just serial without wires. I would avoid BLE(BT4.0) with Android.
For input, begin with a standard Bluetooth terminal app on the phone. I recommend Kai Morich's Serial Bluetooth Terminal https://play.google.com/store/apps/details?id=de.kai_morich.serial_bluetooth_terminal&hl=en_US
Finally, replace the generic Bluetooth terminal with a custom App Inventor project. Configuring a button to send the time/date picker values is pretty basic, and there are many app inventor examples and tutorials on the web.
Good luck with your project, and the key to success is proceeding in small steps and testing as you go.You might want to review this guide to Planning and Implementing an Arduino Program