Can't you just put a local SIM in you phone? If you want to keep your home number alive, you can also buy a cheap phone for when you are in Shanghai.
What kind of use do you need?

The reason such services don't exist (or are underutilized if they do) is because it is super easy to do data on your own in China.

All you need is a phone, from which you can tether.

I used to have a Mifi myself, but I gave up on it once I realized that phones could perform the same mission.

Speaking of Shanghai in isolation, now that the Xiangyang/Fuxing electronics market is closed, I don't know of anywhere in Puxi that sells cheap phones/SIMs, but this shouldn't be a big hurdle.

Any recommendations for telco and plan to use for:

- a three-month stay in Shanghai
- prepaid
- with phoneline and data (using more data than talktime)
- would like to tether to other devices (another phone and an iPad) while on the go

- I don't mind also getting a data-only wifi emitting thing for multiple devices as tethering often can drown my battery of the main device

Thanks!

Unicom set b.

I think that Moondog means China Unicom.

Hmm yes I took it to mean that.

I found the following two plans on their website:
Plan B: http://3g.10010.com/3gindex/3gfee/B_plan.html
Prepaid: http://3g.10010.com/3gindex/3gfee/yu_plan.html

Does Plan B also work prepaid? I've tried to compare it with the Prepaid plans but don't see a huge difference.

Also, can I only get these at China Unicom outlets?

Prepaid and postpaid are effectively the same for both Mobile and Unicom these days (unless you want them to throw in a phone, in which case postpaid with a contract is the only way to go).

As I've said several times up thread, Mobile is more reliable than Unicom (e.g. you can probably get a signal in your building's stairwells, and it works in far flung places), but Unicom 3g supports many more phones than Mobile, and adjusting your plan is super easy (my Mobile number is Beijing based, and I need to go there in person in order to change things... well, there is probably an easier way, but I've never pressed the issue very hard).

I like to buy SIMs at newspaper stands or electronics shops because waiting in line at the official stores sucks. Just make sure to get a 3g number (don't bother with LTE yet; very restrictive, and it probably won't work on your phone).

To be honest I don't really want a second phone and I want to keep my own number in use.

I was not encouraging you to get a second phone (certainly not via a contract), but now that I think about it, since you want to keep your own number active, grabbing a Y1000 (can go as low as Y200) phone from Taobao might not be such a bad idea. The second phone could serve as your Mifi device, and also allow you to do Wechat and make calls.

I pay less than 100 per month, and I've yet to exhaust my data limit. No passport required.

ownership of number
 

One of the major arguments I hear in favor of getting a SIM at an actual Mobile/Unicom store is that doing so attaches the number to you.

But, newspaper stand SIMs are also yours to keep.

Basically, you can officially register them at any point in time by simply answering several easy questions (e.g. who do you call most often?).

My college age niece is spending 6 months in beijing on semester abroad program. Her family is on verizon and she had the iphone 4. In preparation for her trip, i got her an inexpensive Moto G, added her to our TMO family plan for $10, thus giving her unlimited voice/data/text and inexpensive international calling/texting/data plan [almost free except for calls]. A lifeline back stateside as her first trip abroad by herself.

I told her that in all probability she would end up with a second phone and prepaid sim; at the very least she'd get a prepaid sim plan and substitute for TMO. Her reply was the same as yours.....No I don't want to carry two phones, it's a pain in the axx.

48 hours after arriving at school two weeks ago, she bought a cheapie second phone and number [and from a newstand]!

:p

Second phone? I thought that was for 二奶.:p

Of course you are right, but I don't think many foreign visitors fall into the 二奶 or 找二奶 categories. Rather, they want to keep their Verizon phones active, and also make/receive calls without paying through the nose.

There are currently battery cases on offer for most Apple and Samsung phones that facilitate additional SIMs, which solve the problem at hand.

Just wanted to write back about my experiences in getting a China Unicom mobile phone, not under the typical Set B plan vacation plan. In short, I'm having an excellent experience with China Unicom as a long term roaming phone around the world at only $1 month.

So I picked up the SIM in Shanghai HongQiao area under their cheapest plan that cost me only 50 CNY worth of credit to start and the SIM for free. This basic/cheap plan costs only 6 CNY a month and does not include any minutes/data, you pay per use for everything.

Incoming calls are free, outgoing Shanghai calls are 0.15 CNY=$0.02 a minute. Roaming in other provinces is 0.39 CNY a minute. Roaming around the world varies, but I have found it is usually USD $0.15 - $0.25. They send you a Chinese text message with the rates when you arrive in country.

Data pay per use is expensive at 1MB for 1 CNY, but packages can be bought for cheap. The cheapest package is 50MB for 5 CNY. All monthly fees, voice, data charges come out of your original deposit and anything you add afterwards.

If your balance runs out, 60 days later, they close your account. That is why this cheap 6 CNY per month plan is a lot better for long term use than the typical Set B at 66 CNY per month plan. If you leave the country and don't use the phone, they only take out 6 CNY vs 66 CNY a month. Also, one catch is, if you upgrade or start at the Set B 66 CNY plan, they don't let you downgrade back to the 6 CNY plan.

I have also found China Unicom customer support to be excellent in English. In China, you can call 10010 to ask any questions or add data packages. I think English support is only in big cities, so if you are in other provinces, you can call Shanghai support at (021)10010 for English. Also, China Unicom has a global line at +86-186-186-10010 which has English.

Supposedly, China Unicom's world roaming rates are cheap because Chinese nationals are now increasingly traveling around the world. I recently just added 200 CNY to my phone, and figure the 6 CNY or $1 per month is worth it to keep the phone to use both in China and roaming around the world, much better than AT&T world roaming rates.