I do the surveys, the views, etc. while I am playing alt shot. I have had good luck with all of these, keeps me in balls and clubs without buying them. They are often picky about who gets into the surveys and you need to realize that if you go into a survey and answer a dozen questions that is part of the pre=qualification, if you don't get to finish it you get no credits or only 5 or 10.
The best place that I have got lots of credits is doing some of the offers, for things that I was intended to buy anyway, NETFLIX, Shari Berries, etc. Also some of the insurance quotes, etc. will give you a few hundred credits just for requesting a quote.
You can check the status of your credits that you should get from these offers on the offer page.