No, I think I understood you ok. Are we using market/marketing to mean the same thing? To market something or 'marketing' is to promote your services to prospective customers. The client companies want to market to teenagers. You have to use 'marketing' in some contexts to be grammatically correct - to market is the verb, marketing is the noun. You've amended some of my corrections back to your original. Ok, of course that is your choice, but I corrected for grammatical reasons (for example your 'We are looking forwards' and 'if your firm is interested to hear' are grammatically incorrect).
“***“ has specialized in marketing products with the use of text messages. (It does mean what you want when you express it in this way. Marketing to teenagers is the company's specialism). The company has advised a number of British companies to apply (you don't apply marketing, you target it) their marketing at teenagers and youngsters under 25.
We are sure that text messages are the preferred way to communicate among teenagers, who like to be in the forefront of developments, and we understand (no the) young people’s consumption habits and lifestyle.
However the ideal campaign is a combination of advertisements in teen magazines and text messages. The advantage of text messages is, among other things, that you can quickly send daily news and offers to interested young people who are already registered in several clubs. In England alone the membership is more than 1 million.
If your firm is interested in hearing more about what we can do for you, please visit our website. Furthermore we can offer you a personal presentation in your firm by arrangement.
We look forward to hearing from you.