Creating the same, double applications for iOS permitted?
Apple can reject apps which are duplicates:


  2.11
  Apps that duplicate Apps already in the App Store may be rejected, particularly if there are many of them, such as fart, burp, flashlight, and Kama Sutra Apps


Source: Apple App Store Review Guidelines

You should only create one app and spend your efforts promoting this app. Furthermore, if you seek to make apps that appeal to users with clear functionality, Apple's interests and your interests will align. In the case where you are looking to ride hot search terms, unless your apps are really what you are seeding in the search terms - trying to work the system shouldn't work in the long run.