Restful Api & Multi-Vendor License

Can we use RESTful API to build our own web UI application? Does the multi-vendor license allow us to do so?

Also, I noticed that the php language used is a bit outdated, anyone tried to update the php language used for the code?

Thank you.

For that they are preparing the cs cart laravel that will be available by the end of the year. There is a topic inside here that you can check it

Can we use RESTful API to build our own web UI application? Does the multi-vendor license allow us to do so?

Also, I noticed that the php language used is a bit outdated, anyone tried to update the php language used for the code?

Thank you.

Why not? But UI will be limited in functionality comparing with the current store-front