143graphwoman What do you mean by not compatible? Some are, but they require extra setps. For things like MySudo, you will have to create the account on a secondary device and then transfer it to the GOS device. Additionally, for push notifications you will have to have google play services installed. You can still use them without, but you will have to manually refresh to see notifications.
Without knowing exactly what you're trying to accomplish, ill try and break this down to the best of my ability and knowledge.
Firstly, it is very difficult to keep a phone number anonymous, even if you take all of the right steps, there is a chance that the number will eventually become associated with your identity. This is done in many different ways:
Things such as Truecaller and Facebook. Let's say I have true caller and or facebook and I have your "anonmyous number" (and by anonymous I mean you registered it anonymously when you set it up) saved under your real name in my contact list. If I give Facebook or True caller access to my contact list, your name and number are now accessed and associated with your real name. This is what I mean when I say it is difficult, because all it takes is one person using those applications to burn your number.
Calling various services will auto associate the number to your identity. Lets say you call a credit bureau from your "anonymous number" (111-111-1111), you give them your real information over the phone and when asked for a phone number you give them a different number (222-222-2222). You never registered your "anon number", you registered your secondary number, you simply called from your anon number. The next day you call the bureau again, this time you have a generic question that does not need personal identifiable information, so you choose not to give them any. If you call from (111-111-1111) they will answer and say "hello 143graphwomen", because you calling from that number alone from the previous call was enough for them to associate the number with your account and subsequently your true identity.
How to setup an anonymous SIM number:
- Buy a SIM kit in cash (many use Mint mobile)
- Activate the SIM card via the instructions
- When asked for a name, provide an alias name, and an alias email address
- Fund the service by paying with a prepaid visa gift card that was purchased with cash
- There is your anonymous SIM card
Considerations:
- I would not take your old SIM card out and put the new SIM card in at the same location, as cell towers may associate the two since they are going and coming offline/online in the exact same location.
- Once you give this SIM number out, you more than likely, will not be able to keep this number anonymous forever.
- Even with anonymous creation, cell towers could still associate it by location pings. As in, it's constantly pinging at your home every night.
- Remember that SMS is non-secure communication. If you need secure communication you would need to use e2ee (end 2 end encryption), something like Signal. e2ee only works if the people you are messaging are also using the same or similar e2ee applications. Signal encrypts calls and messages, this makes it so that no one in the world can read your messages except for you and the person you are communicating with (exceptions would be if the phone is hacked and the messages are being seen pre or post encryption).
VOIP vs SIM
When you text and make phone calls using a SIM card, your phone is running on the cellular network. VOIP numbers (voice over IP) do not use cellular towers in the same fashion. While they do use cell towers, they use the data only side of cell towers which is routed differently then SMS. VOIP numbers use internet connectivity to send and receieve. All the "burner" apps you tried, are more than likely all VOIP numbers. VOIP numbers are ideal in a few different ways:
- They are more resistant against SIM swaps attacks.
- You can have multiple VOIP numbers per phone.
- Certain VOIP providers allow us the ability to purge things such as messages.
- VOIP numbers are easily burned, so once they become associated to your identity, burn them and get a new one.
- Allows for compartmentalization for increased security against data breaches.
Tieing SIM cards and VOIP numbers together:
Once you have created the "anonymous SIM" service as mentioned above, you will never give the SIM number out to anyone, you will only give out VOIP numbers. This means that your SIM card will strictly be used for data and no calls or texts.
Your threat model will determine if you should even be using a SIM card. I don't know your threat model, so i'm not really going to go into the different strategies regarding SIM vs no SIM, if you feel that your threat model warrants it, i will.
Many prefer the application MySudo, which at the time of this writing is approximately $160 USD a year for 9 VOIP numbers with unlimited call and text and you can choose to use them however you want. MySudo acounts cannot be created on graphene devices atm, but they can be transferred to them. You would do this by using a secondary devices, creating an alias google account, funding the account with google play gift cards paid for in cash, and purchasing the service and then transferring it to your GOS device. Currently, MySudo states that they only store your texts and call information for 24-hours post deletion. Meaning, you can purge your logs, whether that's fully trustworthy or not is at your descretion. Assuming your threat model warrants it, things you're concerned about keeping private should not be transmitted over electronic devices, things that you're not worried about should be transmitted through e2ee messaging devices, and then use your VOIP numbers because society makes you.
Cheers