I will be travelling to China this April (more specifically, I will be going to Chengdu).
As I would need to keep myself updated all the time, and I would need to access facebook and other websites that China blocks, I am planning to buy a VPN package in conjunction with a China SIM card with 3G coverage.
Do you guys have any experience on this? Any VPN and China SIM card that you can recommend?
I've been living in Shenzhen, China, for over a year, here's my experience:
VPN: I believe a safe choice now would be www.julyrush.com. It's the one I've used the most and it works reasonably well.
The most stable protocol is usually Cisco IPSec, since it seems that it's the one with which the Great Firewall has the hardest time blocking, so try to get that working on your devices before you come. L2TP and PPTP rarely work, so don't rely on those. This is true for all VPN services I've tried, not only Julyrush.
I've tried several different VPN services during this year and none of them work very reliably all the time. They change their servers, passwords and ports, and it works fine for a while, until it gradually deteriorates up to the point where it's not very stable (as in, you get disconnected for a moment several times a day, or some servers completely stop working); then they fix it and the process starts all over again over the period of a couple months. Either way, if you just intend to browse websites that shouldn't be a problem at all.
Whatever VPN you choose, however, make sure that you subscribe to it, set it up on your phone or laptop, and test it, because you may not be able to easily access VPN websites once you're in China. Load several profiles for several different servers in case some of them do not work (I have 3 profiles on my phone and i've never had all 3 offline at the same time).
SIM: The only 3G SIM provider in China is China Unicom, that's what you should get. There's also Telecom, I think, but they're CDMA only and I'm not sure how that works. Unicom works pretty well in cities, I've heard that it has much less coverage than China Mobile and Unicom outside the larger cities, but I don't know if this is true (it's never been an issue for me). As a backup, you could also get a China Mobile SIM card which is just 2G, but can still give you some connectivity.
My experience with the China Unicom 3G network in Shenzhen is that it's fast enough (200-500kbps up/down), but not very stable, so it can be frustrating to have a video call while moving. If you just want to connect to a VPN, browse blocked websites, upload photos and chat, that shouldn't be a problem.
On your phone, your VPN connection may drop (it always drops after a while of inactivity on my iPhone), so don't rely on your Facebook app staying connected.
Getting the card itself is easy. China Unicom seems to have the least sales points, but they're still pretty easy to find. You'll see LOTS of China Mobile shops, especially near airports and train stations. What I did was get a China Mobile card first, and use it to look up a China Unicom place on the map. There's also lots of small shops on the streets where you can easily get a card, too, and they usually have signs with the logos of the companies they work with. They may look shady but their cards work.
A few relevant comments: Maps: Google is often blocked here. This means that it may be hard to access GMail, and any other Google services -- including Google Maps.
Maps on your phone can help you out a lot, but if you're using an Android phone, keep in mind that you may need the VPN for it to work properly. Apple's map works great and it seems to me that they're better than Google's, at least in China. On both maps you have a good chance of finding most hotels and a few restaurants (such as KFC or Pizza Hut), in English. You should also bookmark maps.baidu.com, which is guaranteed to work, VPN or not. Keep in mind that it's all in Chinese, though.
Legal stuff: I'm not sure of the exact legal status of VPN's, but their use is widespread, even among Chinese people; and nobody really seems to think they're doing anything illegal. When I was getting internet for my apartment, the internet company itself suggested that I should use a VPN.
Netbars: If you find yourself needing to go to one of those remember to take your passport with you, they are required to request it from you before they can give you access to their computers.
I'd expect that no cross GFWOC (Great Fire Wall of China) traffic is 100% secure from interruption.
2 to 3 years ago I was with a friend who had both a Hong Kong and a Chinese 3G USB modem. The Chinese one was vastly cheaper to use. Well up into Guangjhou the HK one still provided Western Internet access, while the Chinese one never did. We were well beyond single hop cell site range so the HK signal was definitely being relayed through the mainland-Chinese network. This may be a profitable line of investigation. Or not. Chengdu is vastly further in than Guangjhou and they may have their limits on what they allow.
In Shenzhen near the DMZ some hotels have Western capable internet with free WiFi in their public lounges. Whether this facility is available deep in the interior I know not.
Chinese internal internet is horrendously broken by the Great Fire Wall of China. Things that you take for granted either just don't work or walk funny or you get routed to "equivalent services" when you try to use familiar sites. Do not believe shilling apologists who for whatever reason tell you otherwise - unless they have change it all majorly since December 2012 when I was last there.
Superb solution: I got superb results using Team Viewer.
I used version 7 but they now have version 8 available.
I used it from a netbook in China to a LAN in NZ but I imagine that they have iPhone capability. The program effectively gives you the ability to remote control a distant system rather than just to tunnel through the GFWOC and it may not directly suit the mode of operation that you had in mind. It did what it did do in an incredibly capable manner. Remote access to all PCs on a LAN (my wife was impressed (takes some doing with boring things like PCs ) when I freed up space on the WifI connected netbook she was using in NZ while I was sitting in a hotel room in China :-). , file transfer both ways, access to my barred GMail account (not to mention Facebook, Wikipedia, Wikimapia, ...), excellent screen update choices with balance movable between quality and speed. I've used remote control software before but nothing was ever this good.
As I recall, browser operation without install on your local PC BUT you can also leave a sleeping kernel on PCs so that you can access them remotely subsequently.
It is free to download free for non-commercial use and apparently very unconcerned about stopping you using it. It reminds you very pointedly at each startup that if you are using it for commercial use then you need a licence, but it places no restrictions on functionality or length of use.
I'm not sure where the commercial / private boundary is - they are not very specific. I used it when I was absolutely stuck and it made a vast difference to my ability to call home. I was unsure if I qualified as a free user - the friend who recommended it to me has used it with gay abandon for years in all his Chinese business dealings. He assures me he does not match their definition. I'm not so sure.
Pricing seems a bit hard to fathom - they seem to be aiming at corporates, but the cost per user seemed exceptionally high, alas. (Around $1000/user as I recall - if anyone finds that it's $10 do come back and tell me).
