Don't bring data you are not ok with a foreign government forcing you to handover. That's the simplest solution.
Back all your important data up, then wipe your phone before you go. Same with the laptop. You can't be coerced into giving something you don't have.
Threat modeling is important. If your just an average Joe being a tourist it is highly unlikely the Chinese government is going to take your devices to search.
Source: travelled to China for an extended period of time.
Buy and use a burner phone while you're there, and remember that VPNs are illegal.
If you use a sim card from a European country or the US, CA, AU, NZ, JP, etc. all your traffic will be routed through your home country anyways and you won’t be affected by the great firewall.
Do not use any wifi networks ever! Don’t even look at them. Turn off wifi.
Using a SIM card with a decently sized roaming plan is absolutely the way to go.
If you expect them to ask you to unlock your phone for inspection, or will let them take it out of your sight even when locked, take it in with a wiped but not bare profile, then factory reset it and restore from backup once you're through customs. Completely reflashing it would be even better, but probably not feasible unless you're also bringing a laptop.
Edit: oh you have a laptop, in that case go nuts. But the same treatment is possible for a laptop: they might ask you to power it on, unlock it for inspection, or let them take it out of your sight for a short time. Maybe set up a small temporary Windows partition with a few apps and games and innocent docs and pictures. And encrypt the Linux partition, if you haven't already.
Get a cheap phone like a Galaxy A36 for the trip, then install some VPNs with GFW circumvention like Windscribe, Proton and Psiphon before you go.
You should also get a roaming SIM card, preferably from an MVNO or an eSIM app do you don't get rip-off prices.
Roaming SIM cards usually route traffic through their native network like a VPN which bypasses the GFW and gives you some extra privacy.
And once you get there, don't say anything negative about the Chinese government or politics.
Watching YouTube videos and reading posts here about unrelated subjects is okay as long as you are using a roaming SIM card, a VPN or preferably both togther.
All Things Secured tells a story of what happened to him while living in China. https://youtu.be/wOwZ276vo-M
Privacy has become a very important issue in modern society, with companies and governments constantly abusing their power, more and more people are waking up to the importance of digital privacy.
In this community everyone is welcome to post links and discuss topics related to privacy.
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