There is not here a tourist trap, as I know about it.
But there is something that foreigners can think as deception. People are very friendly, but I found that many of them (us) find difficult to answer on question: "Can you help me, where is..." even if you use a Serbian language. Usually, they offer to walk with you to that place instead to explain. This is not touristic trap! My theory is that main reason is some kind of lack of usual conversation about localization because we live in small places with familiar surroundings. Anyway, that is changed. Tourism is very promising area of development for whole Balkan, at least I hope it would be. Cyrillic is not the obstacle, like in many other non-English and non-Latin area. I understand it is challenging but it could be fun and useful to learn the alphabet.
Unique Suggestions: Buy or take a city map in touristic office in city center and avoid to talk with locals.
Fun Alternatives: Buy or take a city map in touristic office in city center and avoid to talk with locals.
The one thing you can be absolutely sure about in Banja Luka is that there is no possibility of getting caught in a tourist trap. They hardly know what a tourist is. The city does see a high proportion of visitors associated with NGOs, charities, etc, but Bosnian traditions and culture seem to be little diluted by foreign influence.
English and French speaking travellers will certainly know they have arrived in a different country. Their languages are not usually anyone's second language and sometimes not the third, or even fourth. But most schoolkids, if not their parents, will know enough to get you by.
As far as I am aware, neither Banja Luka nor anywhere else in the Serb Republic has either a Macdonalds or a Starbucks. It's worth the journey for that alone.
Credit cards are not widely accpeted at stores, and there is only one ATM set in the city. However, you can get cash advance with your credit and debit cards (Visa, Mastercard, Maestro) at any of these banks: Zagrebacka banka, Raiffaisen bank, and Nova banka.
In Banja Luka tourist traps still not exist.
I recommend to watch your belongings from small thiefes in big crowd and other usual precautions, of course.
Also, if you can - avoid to...