Initial Data For Offline Mobile Web App

I have a website with basic information and links. I want to convert this to a webapp and be available offline.

My only question is: Assume the person has internet and dowloads the app. They lose internet and open the app the first time without internet. Will there be anyway to have the initial “templates” filled in with the website data?

Thanks.

save the data with something like LocalStorage or IndexDB then load it on startup

I am not exactly looking for data storage (per say). I am looking for the html templates to have been rendered/stored locally and packed in the download from the app store for example.

Are you saying that the client should have all the html template rendering capability without the server (assuming that I load on fallback) to one of these services? If so, my only question would be what is the right way to determine fallback capability (ie: what status or method do I call to see if I have connectivity before using local).