The above.phone will work without a SIM card. You can connect to Wi-Fi networks to use any of the applications on the above.phone. Your Above Services Suite (email, chat, video conferencing, and search) should all work.
Using cellular calls and texts from your SIM card is insecure, these methods have lackluster encryption and can be intercepted by your cellular service provider or other entities.
Using your Above Services on WiFi gives you multiple layers of protection, encrypting your traffic and hiding it from outside parties.
If your phone service is registered under your name, know that using a SIM card will de-anonymize you as each SIM card is unique and broadcasts its identifier to your cellular service provider.
So how can I make phone calls without a SIM card?
When using the cellular service directly calls and texts are tracked by the provider. Whenever possible, try to use encrypted internet-based communications along with a VPN to protect your internet traffic.
Without a SIM card you can still use a VoIP service, like JMP.chat & XMPP to call and text over the internet, effectively giving you fully functional phone that is not tied to a SIM card! The Above Privacy Suite provides a private XMPP account, as well as 1 free month for JMP.
What about data-only SIM cards?
The big privacy issues with SIM cards are connected to the phone number & calling functionality of them. Phone numbers can serve as identifiers calls & texts that are made and received can be directly associated with this identifier. Furthermore, cell tower triangulation can assess the location of a SIM card.
However, using the data part of a SIM card is a different story. Since the data is transmitted over the internet, it allows to not only use more private, encrypted communication platforms, but also to route the data through an encrypted VPN service. It also makes it possible to use an internet-based virtual phone number service, like JMP.chat! Users of the Above Privacy Suite will not only get access to our private VPN serivce, but also to an XMPP account and 1 free month of JMP!
We do offer a data-only SIM card of our own - the Above SIM.
(note that it requires an active Above Privacy Suite subscription)