"Something based on Cordova (eg PhoneGap, Ionic) with Crosswalk can get you to about 90% of the performance of a native app, with about 1/2 of the development time because it's all built with web technology."

This is true only if you're working with people without experience. Someone who is experienced with the mobile toolkits is going to be able to develop the app just as fast, with more functionality.