My local coworker taught me that all 3 carriers have a 8RMB plan that has minimal data like 100-200MB with either 0-10 min voice or free caller ID. Because how China treat mobile phone number as ID and porting number is difficult, many people keep their number on the 8RMB plan, and just add a second line when they jump from plan promo to promo, or carrier to carrier. I wouldn't mind pay 10MB for maybe 0 min/ free incoming SMS and 500MB of data. It would be enough to cover my data needs when I am in China for a trip, and cheap enough not to even have to think about it.

The 200MB of data a month is just enough for me to do a Baidu map search or tranceive some WeChat message. The issue all Chinese apps are are like ad-machine... Those ads use up soooo much data more than the actual task you are trying to carry out, so 200MB would go very quickly. I have my phone setup to restrict mobile data on everything except WeChat and AliPay.

Because of your previous advice, I did try get a few SMS while in the US, and havne't seen any extra money deducted. I will know for sure by the end of the month when the account cycles.