EVERYTHING that sandboxed google play has access to?

TroublingCoronary63

I read through many threads on here and reddit and I've read the GrapheneOS documentation but I couldn't find a complete answer

If I install Sandboxed google play, play store and google maps in a profile, what can google access?
Play services has network and notification permission.
Maps has location and sensors.

What can google access? Any telemetry or device info?
Can they read notifications?
Can they access content from other apps? I don't think so but can they access content from other google apps? Like camera for example?
Is there anything else they can access?

Thank you

DohnJoe

TroublingCoronary63

You specified notification and network permissions, so I will assume you didn't give sensors.
With this permissions, the app can only:

show notifications (but not reading, that is another permission)
connect to internet

It's this simple :)

Starting with android 17, LAN connectivity is done via Nearby Devices permission, so they shouldn't be able to what's inside your network.
Corollary: if you use a VPN, your LAN visibility is managed by the VPN.

Regarding connection to other apps, there is the Inter-Process Communication (IPC) mechanism, which allows 2 apps to talk one with another.
This is not intended to move a lot of data and to work it needs both of the app to willingly "connect" and send/receive data.
Consider that if you try to send more than 1MB youi get the TransactionTooLargeException error.

This means that technically your Google Camera app would be able to send data to another Google app, but there is no proof this happened in the past.
Also, Google has GPS and GMF unrestricted in almost every smartphone in the planet, allowing them to collect all the data without an IPC fallback, it is very unlikely they build an IPC mechanism to grab data from other apps in their suit.

To be more verbose: having a 1MB limit per transaction, it means that to move a single 20MP picture, you need several transactions.
To manage this transactions you need more code that checks for integrity of data, plus a system that have to understand which apps are available for this IPC comms and then some code to try to exfil with internet permission (if available).
If not available, the app should try another one, and so on.
All of this code cannot be hidden with magic, and if they implemented it we would have evidences for sure.

GrapheneOS

TroublingCoronary63 The whole point of the approach is these are regular sandboxed apps with absolutely no special access. By asking this specifically about sandboxed Google Play, you're implying you don't know the basics of the features.

What can google access?

Only what regular sandboxed apps can access, nothing more.

Any telemetry or device info?

There's no OS telemetry to access. Hardware identifiers aren't accessible to regular apps. There's a special case for an SMS/MMS app and there's a special toggle for granting ICC authentication access when using Google Messages but it's not relevant if you don't grant it.

Can they read notifications?

No, apps can't see notifications without you granting access to the special access permission for it. Many apps use Google Play for push messaging but they can use empty push messages (Signal) or encrypt their data through it. It's no different from how apps can use UnifiedPush.

Can they access content from other apps?

No, apps can't access data from other apps.

I don't think so but can they access content from other google apps?

Only what those apps explicitly choose to use it for within a profile, no different from how other apps work.

Like camera for example?

Camera access requires the camera permission which also requires that the app is in use.

Is there anything else they can access?

Nothing more than other regular sandboxed apps. An example is being able to see which other apps are installed in the same profile. None is specific to Google Play.

TroublingCoronary63

Thank you both for your helpful answers.

GrapheneOS

So do I understand it correctly that there's basically no privacy difference between having play services installed vs having it not installed?

Kamika242

GrapheneOS

Great explanation, thank you, also for your patience on repeated questions like this!

GrapheneOS Nothing more than other regular sandboxed apps. An example is being able to see which other apps are installed in the same profile. None is specific to Google Play.

As I understand this, per example Signal would see, that Revolut is installed in the same profile, Playservices would see it too, but does Playservices automatically send the whole list of installed apps to Google, with or without having a Google account?
When I see in RethinkDNS, how many Google apis are called regularly by Playservices, even only with given network permission, there must be a lot of data sent to Google. This mainly affects people who doesn't use the "No Google" blocklist.

de0u

TroublingCoronary63 So do I understand it correctly that there's basically no privacy difference between having play services installed vs having it not installed?

Most people install Play Services to satisfy one or another app. Interacting with apps that rely on Play Services to go about their business is fairly likely to convey some information to Google -- maybe more, maybe less, maybe complying with their published policies, maybe not. Every time an app uses Play Services for something, even if Play Services doesn't know exactly what it's doing, there is at least some telemetry (date, time, IP address, whatever).

Overall, using anybody's software, when the software is designed to access remote resources, probably has some privacy implications. That applies to an app using Play Services and to Play Services itself.