Can you delete data from google sheets or will it mess up typeform?

@joinjade - welcome to the Community! 

this comes to you from a user of the tool. 

I use Google Sheets a lot with the tool and during the testing process for my forms I have deleted a lot of the rows of data from the GS (not the header row !!!) and have not had a problem with the Google sheet functioning. 

I use additional tabs to extract the raw input data and do any transforms and reporting - especially field names, to make them shorter and easier for my brain to deal with them during reporting. 

If you run into any issues with your typeform dumping data into the google sheet after you do delete something, simply delete the integration in Typeform and recreate it. If you desperately want to keep the same sheet name and you have done anything to the Google sheet that you want to keep (on additional tabs etc) i suggest making a copy of the Google sheet under a different name and then creating the integration and sheet again from Typeform - then copy the details from the old sheet to the new sheet. 

there may be other best practices and guidelines from the Typeform folks (officially and they are great resources!!) but that is my experience to date

des