If you are a developer start creating small things. Don't go jump into a large web app. Small bites will help motivate and create a momentum so you can start doing bigger things.

For example, last year I created a couple of jQuery premium plugins, I putted a price tag on them and offer user support. Some of people said "no way, your plugin will make it, there will be free version of it anytime soon".

Guess what ? Almost one year has passed, there aren't any full featured alternatives and I'm making a $xx bucks on a daily basis. I'm not making $50, but it's close tho. For the effort I've put into it I pretty happy with the outcome. Clients appreciate the fact that I offer support, and the best thing is, I haven't yet give any support because none of my clients have request it so far.

In a nutshell, my best advice for you is: - Start by doing small quality things. - Create a solid client base, keep them happy and show them what you are doing currently

Soon enough your will start see some profit.

How many plugins did you write? Also, how do you handle payment, licensing and such?

Making about $40/day extra would help a lot currently and I'm not bad with jQuery. I can probably hack together some simple yet usefull php scripts too. Wonder if those would sell?

I currently have two plugins. I use paypal to handle my payments, and I have a normal copyright license for users, nothing major really.

Like I said, keep it simple and launch it. Agile way ;)

Don't sell yourself short, all of these options could easily bring in more than $50 per day.

Think about your current skill set versus what you would like to learn that would help your career and future earning potential. Balance those two items to help you choose.

If you have an interest in all three develop all three ideas over time.

For the short term I would pick the area that you are most skilled in so you have the best chance for success.

Digital content probably has the best chance for success depending on your knowledge base and target audience. An e-book could be put together fairly quickly. Pick something you are passionate about and put one on the market and see how it goes.

Web Apps are great for reoccurring revenue, the software as a service model is one of the best business models out there. Find a problem and solve it with a web application.

Apps would be the most difficult to break into and have a money maker the first time. It's definitely a high demand skill and something you should develop for the future if you have an interest.

Recommended listening for inspiration:

http://mixergy.com http://37signals.com/podcast#episode5

You mention Mixergy and 37Signals, but http://beyondthepedway.com/ seems to hardly ever be mentioned. Great stuff there as well in my opinion.

Are you looking to learn new skills or to make money? Learning something new is not going to bring you $50 / day now, but on the long run yes it could turn down to $500 / day or more. With that said I would suggest looking into the mobile industry iPhone and Android for now (the other mobile OS are not worth the time and effort, the manufacturers will create a true OS pretty much soon - if they wake up from they're dream " We have a mobile OS").

A lot of the content on the web today is getting much attention from smartphones, so there is a ton of potential out there.

Hope this helps

> ebooks on easy to learn and write about topics

This can provide some very interesting options (and lucrative, affiliate) revenue streams; possibly generating passive income for years to come.

People (read super aff marketers) have written eBooks on this very topic i.e. how to build long-term, passive income streams with eBooks - if you scout around a bit, I'm sure you'll find a few.

HTH

My advice to you is... try as many small ideas out as you can, see what does earn a bit. It's not that hard to get something earning a couple dollars/day, just doing it again and again is the hard part.

Aren't payment processors a pain?

From my experiences, they make you create terms of service for every web app no matter how tiny. Are there ways around this and what do you suggest?

Perhaps. But don't let that limit what you can do. Monthly cost is 1$ but you need to pay for a full year in advance.

For something with almost no delivery cost (digital content), as long as you're clearing transaction charges, you are still making money, right?

Maybe money isn't in charging for the apps at all? What about ads? Lead gen? Affiliate Programs?

There are tons of ebook money plans/schemes - go hunt around blackhatworld.com and read some of the threads there. Some are nonsense and some are legit.

Why is your goal to make $50 a day?

Assuming he makes $50 every day for a calendar year, we're talking a little ways north of $18k/yr, before taxes. Not the biggest amount in the world, but certainly pretty substantial by any reasonable metric.

Alternatively: $50 seems to me like a pretty reachable number, while still being large enough that it's not immediately reachable.

Though I won't presume to know the OP's motivations.

Yeah, but his purpose behind wanting to make $50 a day can dictate how you want to get there. Do you want it to be a sustainable $50 or are you trying to reach that goal to then expand beyond that $50? Whitehat / blackhat $50 a day?

So, the why is important for me to suggest to you how :)