Hello Sameera,

I would like to tell you that the choice varies from person to person.

All of the apps have different ratings and some people may like/dislike a particular app.

So it comes down to you that do you like the features it provides you and thus it really help you in GK.

I would like to add that preparation for General Awareness is not a matter of 1 or 2 months but a continuous process so you have to work hard daily

Subscribing to one general newspaper will help you more. For in-depth subjective knowledge, you can always rely upon good magazines like Outlook, The Week, The Economist and, many more

I would suggest you visit the careers360's link given below for an in-depth of of General Awareness tips for MBA.

The link for the same is:https://bschool.careers360.com/articles/general-awareness-for-mba-preparation-tips-and-exam-specific-analysis

Hope this helps and all the very best to you!