Unfortunately, this app cannot be operated from a computer.
However, you can export your data and use it with other services.
Data export is part of the paid Premium Service. Tap "Premium (No Ads)" at the top of the Settings screen and purchase the Premium Service. Then "Backup All Data by Zip file" near the bottom of the Settings screen becomes available for exporting your data.
When you tap this button, each diary entry is saved, photos included, in the file format you choose (HTML, PDF, RTFD, or TXT), and everything is exported as a single compressed Zip file.
You can send the Zip file by email, save it to the Dropbox app, transfer it to a PC via Bluetooth, and share it in many other ways.