Nokia Mobiles could probably unveil the Nokia Lumia 525 codenamed Glee and upgraded version of Lumia 520, this October at the Nokia World event in Abu Dhabi. This info is still a rumor and was leaked by @evleaks.
If @evleaks are to be believed the new model will be called Glee a.k.a Nokia Lumia 525, a successor to the most popular Windows phone the Nokia Lumia 520. Incidentally the Lumia 520 was very popular in India, specially for its price tag. 520 not only helped Nokia regain its brand image but also made Windows OS as the second most popular OS in India.
If you may recall the Nokia 520 was priced under Rs. 10,000. The new version i.e. 525 will take over from where 520 left and probably we could find some new features and hopefully with an affordable budget. Stay tuned for more.