AWS App Mesh vs Istio: What are the differences?
AWS App Mesh: Easily monitor and control microservices running on AWS. AWS App Mesh is a service mesh based on the Envoy proxy that makes it easy to monitor and control containerized microservices. App Mesh standardizes how your microservices communicate, giving you end-to-end visibility and helping to ensure high-availability for your applications. App Mesh gives you consistent visibility and network traffic controls for every microservice in an application. You can use App Mesh with Amazon ECS (using the Amazon EC2 launch type), Amazon EKS, and Kubernetes on AWS; Istio: Open platform to connect, manage, and secure microservices, by Google, IBM, and Lyft. Istio is an open platform for providing a uniform way to integrate microservices, manage traffic flow across microservices, enforce policies and aggregate telemetry data. Istio's control plane provides an abstraction layer over the underlying cluster management platform, such as Kubernetes, Mesos, etc.
AWS App Mesh and Istio can be categorized as "Microservices" tools.
Istio is an open source tool with 18.5K GitHub stars and 3.1K GitHub forks. Here's a link to Istio's open source repository on GitHub.