Yes, there are a number of similarities. Both of us run an LSP and user nodes only connect to the LSP(s). But with Phoenix, the Lightning node runs on the mobile device, while with Lexe, the Lightning node runs inside an SGX enclave in the cloud; the mobile app is mostly used to remotely control the node (after the node and mobile app mutually authenticate each other of course). This difference in architecture allows us to help users receive payments when they're away from their phone.