Switching to ads is a very difficult way to sustain your current ~$1200/month, much less grow it.<p>I created a bedtime calculator called <a href="http://sleepyti.me" rel="nofollow">http://sleepyti.me</a> that usually brings in about 10k hits per day. At that rate, I earn between $10 and $20 per day, or $300-$600 per month. Although I consider that revenue to be an astounding success, it is less than half of what you're making right now through the few customers you have.<p>I agree with cabinguy that a free trial system seems to be your best bet. Don't pull a bait-and-switch with the prices, but offering a 1 month trial that shows how easy and efficient your app is seems like a great way to hook potential customers. Maybe your price point <i>is</i> a little high, and you could be willing to let customers wrestle it down to, say, $200/month. Pricing is difficult, and especially without knowing your niche it's a little hard to say, but the rule of thumb is that if people say it's too expensive, it probably is.<p>Alternatively, you could meet somewhere halfway and offer a six month "special price" at $100/month or something to see if you can hook people in that way. Either way, I wish you the best of luck!