When your app behaves in sandbox mode, it’s restricted compared to normal behaviour. In particular (quoting from the API docs for the sandbox):
The API behaves as if the only users on Instagram were your sandbox users, and the only media ever posted were the last 20 for each of these users.
So the API can’t see posts that the user has liked if those posts were made by non-sandbox users.
Here's a scenario:
Assumptions:
- Say there are 100 instagram users all over the world(I know its more, just for example's sake!).
- An app named APP1 is live and not in sandbox mode.
- An app named APP2 is in sandbox mode[meaning not live yet!].
- There are 5 verified and registered sandbox users for APP2.
Now, as Instagram document has said: Here will be the black box flow.
Situation 1:: APP1 tries to accept user likes for sandbox/non-sandbox users - Result: it gets their data. Reason: For live apps, number of users visible to the app is the the number of users available on instagram.
Situation 2:: APP2 tries to accept user likes:
For sandbox user - It will get only those data(likes here) for which the users are registered as sandbox users for this app. Any other likes for non-sandbox users will be not visible here. {As if 5 users existed, if any users like any content of those 5 users, it will be visible.}
For non-sandbox users - Users are not visible!
I missed the last part of visibility, which took me some research and co-relation to find out. I guess there might me other developers who might have not understood the sandbox user's visibility part of the document.