What I've wondered so far is if there is a way to substitute uploading csv files(containing Mobile Device IDs) manually to create a list(for remarketing) with using APIs(or etc.) as below.
Let me share my plan to do this.
After extracting Mobile Device IDs from our own database, we'd like to directly send this info to Google side through Google Ads APIs.
(Currently, we extract tons of files from the database, and upload these one by one, which takes a huge while T.T)