At 12 cents a day, I guess you are looking at the Azure Basic SQL Database instance which would be the cheapest SQL instance available. You won't get SQL any cheaper than that. I took at look at Azure PostgreSQL and MySQL and I don't think that would be any cheaper.
Since you are looking at "Basic" storage, I will assume this isn't a business-critical app, or you have some flexibility in terms of response times. With that in mind, a cheaper option would be to use Azure Table Storage. I believe Basic Azure SQL database has 2GB of storage. 2GB of table storage would cost around 13 cents a month (~0.0044 cents a day). My team has used table storage as a low-cost simple database for apps in the past. If you have a single table of data, then this is easy. If you have multiple tables and want to do table join queries, then it gets a bit trickier and requires making multiple requests and manually joining the data.