Talking about encryption is difficult because while it's crucial for security and privacy, most people don't understand or care about it. Despite its importance, there's always a trade-off, since it takes a (sometimes hefty) toll on system resources. This can make a device practically unusable with how it slow it is due to the encryption processes. To combat this, Google announced Adiantum, a new mode of storage encryption for low-power devices like Android Go phones, smartwatches, and so on.
Our higher-end phones have specialized hardware that handles encryption, which used the Advanced Encryption Standard (AES). Budget devices that use less expensive SoCs don't have the capacity to use AES efficiently, so Adiantum is meant to fix that. The way it works goes way too far down the rabbit hole for AP's scope, but there will be more in-depth information if you're interested in the second source link below. Here's a brief snippet if you don't want to wait:
"Adiantum allows us to use the ChaCha stream cipher in a length-preserving mode, by adapting ideas from AES-based proposals for length-preserving encryption such as HCTR and HCH. On ARM Cortex-A7, Adiantum encryption and decryption on 4096-byte sectors is about 10.6 cycles per byte, around 5x faster than AES-256-XTS.
Even though Adiantum is very new, we are in a position to have high confidence in its security. In our paper, we prove that it has good security properties, under the assumption that ChaCha12 and AES-256 are secure. This is standard practice in cryptography; from "primitives" like ChaCha and AES, we build "constructions" like XTS, GCM, or Adiantum."
The hope is that Adiantum will make it so that anyone who coming online for the first time, or even those that have already started, can share in the security that encryption offers, even if their device isn't very powerful. It's a noble idea, though it has other applicable uses for smartwatches, TVs, and connected medical tech, too.