Is it logical to load all the available data from the api and then work with them, or is it better to load them as needed?

Question

iOS

I'm making a stock monitoring app.
What is the best way to work with general information about promotions.
Is it worth downloading all the general information at once and then later, for example, when searching, just go through the array of stocks, or is it better, let's load the 10 most popular ones from api, and load the rest as needed?

Answer 1

it depends on the type of your application, if the application must work offline, then you need to save it, if only online, then you can not save it.
in any case, if you decide to save data to the device, you immediately have conceptual questions, such as: when to synchronize data, how to display data if synchronization has not yet ended, and the data should be shown, how to update / synchronize data changed by the user, etc. Yes ,
and the local storage mechanism itself and its correct operation require a fairly high qualification of developers.