It sounds to me like you’re referring fairly specifically to the the marketing firm ComboApp specifically mentioned in the Bulletproof Outlaws blog linked to in the other thread yavadoo. If that’s the case, the guarantee they make is actually quite narrow. Specifically, if you hire them for their “Top 100 Campaign” they guarantee they will get your game into a single top 100 in a single category on the Apple App store. They do not offer services specifically geared for the Android market. Importantly, they don’t guarantee they will keep you there for any length of time. This means they are promising they will for example, get your game into the top 100 of the “arcade” category on the iTunes app store for a single day. This in no way means you’ll be anywhere near the top 100 of the overall app store or even the overall games category. Further, this service costs $4,900 and not everyone can get it. They state you must submit your game for their review and they must agree to take you on as a client for this particular service (other services they offer have no such restriction). This seems a clear statement of the fact that not every game that might look for them to promote it is top 100 material, and they’re going to try to avoid backing a loosing horse. If they fail to meet this promise, they refund half your money, $2450.
I’m personally not so down on marketing firms as the other posters here seem to be. Various businesses I’ve worked for over the years have hired marketing firms to promote their products and most continue to do so. Not all of these companies hiring PR firms were mega-corps like Coke, some were much more modest in size, (though still far larger than a single indy developer.) The reason these companies continue to hire marketing firms is they believe there is value in doing so. Two different friends of mine are in marketing, and though they’re of course biased, both can make strong arguments for the value of their services.
Marketing is a business that relies on specific skills and even more importantly, connections. Most game designers have neither of these, so it might make sense to hire someone who does if you have the budget. Know what you know, know what you don’t know as they saying goes. If the principals of this marketing firm have connections with editors and reviewers at important blogs, this could be worth the money. BPO mentioned repeatedly and specifically how he saw spikes in his sales when he received favorable reviews at larger blogs and sites. Also, they do things like bombard the internet with press releases, and make target advertising buys on your behalf, so they’re not just sitting on your money. You could do press releases and buy advertising yourself, but a firm that specializes in marketing apps is probably going to be better at writing press releases and getting them into the right hands, as well as knowing what advertising tends to be more effective than another.
I’ve done some preliminary due diligence on ComboApp, as I like you have considered using them or another firm like them. What I’ve found so far is ComboApp has been around for at least two years, and does have a verifiable list of clients. This is a good sign as it means they’re probably not a fly by night operation or a complete scam. I have not as yet contacted any of their past clients to ask them directly for their experience with ComboApp, but if I do consider moving forward with them, I certainly would and would recommend you do the same. I’ve cross referenced the time period ComboApp was employed by these various developers with stats available on App Annie to see if I could find any correlation between increased sales and hiring ComboApp. In some cases there does seem to be something of a correlation, but in most cases it’s entirely unclear. In ComboApp’s defense, many of these past clients hired them for relatively smaller services such as writing and submitting press releases. I have not yet been able to find a client who hired ComboApp for their top 100 campaign, and before I did, I would insist on them providing such references which I would verify personally. ComboApp does to their credit provide a list of past clients on their site, and more can be found with some googling and blog crawling.
So, there it is. Always do your due diligence before hiring anyone, but they, or another marketing firm may not in fact be a bad investment of marketing dollars. Also, make sure you’ve actually spoken to some of these past clients yourself before you hire anyone. Keep your eyes open. If I go forward with a marketing firm when the time comes (still a fairly long way off for me), I’ll be sure to post my experience on this forum for others. If you go forward with ComboApp or another, please do the same, the rest of us would love to hear your thoughts.
Cheers!