So will my usual apps actually work?

The honest answer: on a roaming line they often do, because your connection exits through an overseas network, but nobody can guarantee every service at every moment. The safest move is to save offline maps and key info as a backup for when something won't load.

Do I need to bring a VPN for mainland China?

On an overseas roaming line, the everyday apps most travellers use tend to stay reachable without extra setup. But because nothing is guaranteed, the most reliable move is to save offline maps, your hotel address and return travel as offline files before you go. Whether you need any other tools is your own call, based on your needs and local regulations.

Will WeChat and Alipay work there?

These local services generally work as normal on the ground. The tip is to register, link your cards, and log in over Wi-Fi at home before you travel, so you're not stuck on an SMS verification or a download once you arrive.

Does Hong Kong need any special prep?

Not really. The networks are mature and the services people commonly use are generally available as normal, so it feels much like anywhere else. Prepare as you would for any travel eSIM.

Can one card cover both Hong Kong and the mainland?

It depends on the plan's coverage. soda is simpler here because it isn't tied to a country and bills by actual usage, so as long as both places are in the supported area, it's one tab the whole way through.

China eSIM without a VPN: will your apps work?

On a travel eSIM that runs over an international roaming line, the everyday apps you normally use will often still work in mainland China, no VPN needed, because your connection goes out through an overseas partner network. One caveat before anything else: no eSIM can promise that a specific service will work or stay fast, and conditions change over time and with the network on the day. This guide explains, in plain and neutral terms, how it generally works, how Hong Kong and the mainland differ, and what to prepare so you aren’t caught out.

Why it works without a VPN: how a roaming line exits

Let’s unpack the jargon first. When a travel eSIM uses a roaming line, the profile on your phone doesn’t sign you up as a local subscriber on the ground. Instead, it connects through an overseas partner carrier’s network. Your data effectively travels back to that overseas partner’s system and reaches the internet from there.

That one detail (your traffic exits through an overseas network) has a practical upshot. For a lot of travellers, the maps, messaging, and social apps they rely on tend to remain reachable without any extra setup, and the experience feels close to what it is back home. The reason isn’t complicated: your connection is going out over that overseas path rather than through the local on-the-ground environment.

Keep two caveats in mind. First, this is “usually,” not “always.” Different plans use different overseas partners, so behaviour varies. Second, network conditions shift, so smooth today doesn’t mean smooth every day. The right mindset is “here’s how it generally works,” not “here’s a guarantee.” If you want the groundwork on how eSIMs differ from physical SIMs, start with eSIM vs physical SIM.

Hong Kong and the mainland aren’t the same

They often get lumped together, but for a traveller the day-to-day experience is genuinely different.

Hong Kong is the simple one. The local networks are mature and dense, the international services people use day to day are generally available as normal, and there’s nothing special you need to route around. Signal in the city, the metro, and malls is solid.
Mainland China is where the local on-the-ground network environment may differ from what you’re used to, and some overseas services you rely on aren’t always convenient to reach over the local network. This is exactly where running over an overseas roaming line makes a practical difference for travellers, because your connection exits through an overseas network. Same disclaimer applies, though: it varies by plan, by time, and by the network on the day, and nothing is guaranteed.

In Hong Kong you barely have to think about it. For the mainland, keep a backup ready, which we’ll get to.

Three ways to get online, compared

How you connect	Hong Kong	Mainland China	Watch out for
Travel eSIM on a roaming line	Smooth and easy in general	Everyday apps often reachable, but not guaranteed and conditions change	Check which line the plan uses
Local SIM / local plan	An option, purely local connection	Local network environment differs from what you know	Registration and ID, more effort
Roaming on your home number	Convenient but pricey	Convenient but pricey	Long trips hurt the bill

The takeaway: travellers mostly want “land and keep using things as normal,” and a roaming line tends to fit that best, as long as you accept it’s a general pattern, not a promise.

What to prepare before you fly

However smooth the connection, offline prep is the cheapest insurance you can buy. The items below take only a few minutes and will save you if a service won’t load or you end up somewhere with weak signal.

Download offline maps. Save the area you’re visiting as an offline map so navigation and finding your way still work even when the live connection is patchy. This is good practice in any country, because maps lean heavily on a stable connection.
Save the key info. Your hotel address (ideally with a local-language version too), booking confirmations, the return journey, and emergency contacts: screenshot them or store them offline. Don’t let something as small as “looking up the address” get stuck behind a dead connection.
Log in and update apps first. Before you leave, on Wi-Fi at home, sign into the apps you’ll need and update them to the latest version, so you’re not stuck on a verification screen or a download later.
Note the line type. Before buying, check whether the plan is a roaming line or a local line, because it directly shapes your experience.

How much data should you get?

This depends far less on the destination and far more on what you actually do. Map navigation is cheap; the real data hogs are video, video calls, and sharing a hotspot with the people you’re travelling with. An average traveller runs roughly 0.8 to 1.5GB a day, less if you lean on hotel Wi-Fi, more if you stream all day. For a full breakdown of what each activity costs and how to size your own day, see how much data do you need.

One thing people overlook: photo auto-backup, app auto-updates, and cloud sync quietly eat data in the background. Set them to Wi-Fi only before you go and you’ll save a fair bit over a trip.

How soda works here

soda’s design fits this trip: a steady connection as the floor, on stable, quality partner networks, which matters most to travellers who want to land and keep using things as usual. The bigger relief is that you don’t pre-pick a “Hong Kong plan” or a “China plan,” and you don’t guess at GB. You land, open it, and get billed by actual usage. At settlement, soda automatically applies the cheapest combination of plans in retrospect, and the balance never expires. The light day in Hong Kong and the heavier days on the mainland all go into one tab, so you never lose out because one stretch was hard to predict.

soda makes no promise that any particular service will be reachable, because that genuinely shifts with network conditions. What it does offer is a stable line, pricing you can actually read, and one card even if this trip also takes in Japan, Korea, or Thailand. If you’re crossing several countries, see one eSIM for a multi-country trip.

If you want to think through the whole online setup before you fly (whether to bring a second phone, how much data to size), cross-check the per-activity breakdown in how much data do you need.