SIM cards are the lifeblood of our mobile, linked lifestyles. These small modules let users to accept phone calls, send text messages, and connect to a variety of internet services. They're so important to phones — both feature phones and smartphones — that manufacturers must find a way to fit them in, regardless of size limits. As a result, the form factor has shrunk from full to mini, to micro, and finally to nano SIMs. Some phones now include embedded SIMs (eSIMs) that can replace regular cards. Unfortunately, there are a few issues with eSIMs that may prevent them from entirely taking over — but it appears that Google may have some fixes ready in Android 13.
The main issue here is figuring out how to provide something resembling dual-SIM compatibility with eSIM chips that only handle a single subscriber line at a time. As described by Esper's Mishaal Rahman, Google's approach leverages what it terms multiple enabled profiles (MEP) to support many active SIM profiles on a single eSIM. To put it another way, a single eSIM element will be able to connect to two distinct carriers at the same time.
The fact that everything takes place on a software level is what makes Google's MEP technique so intriguing. While only one genuine physical connection exists between the components, many logical interfaces function as distinct communication routes between a SIM profile and the phone's modem. Google is introducing API classes to AOSP that will allow carrier apps to obtain information about the logical and physical interfaces, as well as the SIM profiles that are stored on them.
While eSIMs may now hold many profiles on a single chip and switch between them, only one profile can be active at any given moment. To put it another way, the only way to acquire dual SIM compatibility with present solutions is to purchase a device with multiple eSIMs, multiple physical SIM cards, or an eSIM plus a physical SIM card.
So, you say, why not just use two eSIMs? That rather contradicts the entire premise of the technology, as having two eSIMs would still limit available space — albeit on a smaller scale than conventional cards.
Everything leads to Google adding this boosted eSIM support in Android 13. According to Rahman's research, AOSP mentions the technology, and the Android Developers website says Android 13 may include it. Some new MEP APIs are currently available in Android 13 DP2. Right now, we're simply waiting for any semblance of it to go online — luckily, A13 betas are just around the horizon.
