I have been working on mobile sector for almost 2 years now, I became a professional on this sector through all the experiences that I gained. I have always chosen legal way to make money (No spamming apps, no adware programming, not lying to my users and customers).
I have learned about mobile advertisement networks in years, these are the mobile networks I used and some of them I am still using.
Intrusive Advertisement. Push and icon ads generally accepted as intrusive ads, yet they have very good income, but it also brings low ratings and bad comments. I personally HATE push ads! However, if the app is useful for me, I never uninstall the app and I do not need to. After a single "Clear" button clears all notification center, this is not a problem. Push ads totally legal and it has been around for a long time. There is one thing I cannot accept, ads without EULA and User Consent, this is illegal and against Google Play Policies.
As long as it is legal and not against developer policies, you can do it. Ethic and moral are important things, but you have to draw a line between ethic/moral and business. Business means "Add Value (Make Money)" for organization under legal circumstances. Using push/icon ads are %100 legal and not against polices as long as you show an EULA and get user consent. If you care about ethics too much, you will lose and will not make money, if you use too much intrusive advertisements, you will lose customers and will not make money. The key is balance, this what major companies and top developers do.
First years and banner ads. In my first years, I never draw a line between ethic/moral and business. I was working on apps for months and using banner ads and some offer walls. I never used an intrusive advertisements, I spent around 6-7 months for my 2-3 great apps. Still I got bad comments, low ratings and etc... My users kind of crashed me down badly.
Business is not what you think. Look at the top developers and major companies, they have lots of free apps with very expensive in-app purchases (it is like a robbery, gems, coins, virtual money etc for $2,$3,$5, $20 etc...) very very expensive, sometimes you have to pay to play more, but it is %100 LEGAL. You have to understand what a business is, the first and golden rule is "Add Value (Make Money)" as long as it is Legal.
Still do not use Push Ads/Icons alot. Intrusive ads maybe legal and makes great money, but it hurts our first rule in the business "Add Value (Make Money)" in long term. Very low ratings and bad comments will effect our organization on along term, and it will reduce our income.
Money makes money, but nothing else. I know many spammers and ad ware programmers makes more than $50,000 every month with no useful apps, no EULA, no user consent. Do you need that much money in this dishonest way? You shall not. Money makes money, and quality is very important, do not be cheap, buy high quality assets. Buy graphic licenses, audio files, images, scripts and so on, find graphic artists and developers.
Start small, not big! Do not try to make next Angry birds, start with small games like a simple tic-tac-toe, puzzles, card games, do not spend months for a game in the beginning as single developer.
You must make money in the beginning! You will earn more and more in the growth, use some push/icon ads times to time, you will need money on the road for expenses, with banner ads in the beginning you cannot even buy a graphic vector license. Be smart, be a businessman and add value to your organization. Use some intrusive ads time to time with legal way and EULA to increase revenue to buy higher quality assets and maybe to give some advertisements, draw a certain line between ethic/moral and business, try to be in the middle.
Customers live in present, not past! In mobile sector reputation changes quickly. Look at first Angry bird, everybody loved it, than that many many advertisements in the app after every level, then users hated this intrusive ads, then they removed some ads in time, and users loved them again. This is what a business is, find the balance with your advertisements. Use intrusive ads time to time legally, and remove them time to time. Balance is the key. I know top developers gets thousands of 1,2 starts because of intrusive ads, and they get 5 full starts after a single update and new features.
What is path to make over $10000 or much more monthly ? Start with small apps and not so much intrisuive ads, then use some intrusive ads to make money and buy better assets and maybe give a litte advertisements, then remove intrusive ads and publish new apps, wait for a growth, use some more intrusive ads to make more money and advertise. On the road buy high quality app scripts, find a graphic artist, build a team if you can. The strategy is as you grow use less and less intrusive ads, change to better ads and in-app purchases.
If you can grow enough. One day you will remove all intrusive ads and you will never ever need them again, you will have ads from companies directly without using any other ad networks, you will have in-app purchases which will make a lot of money for you. Banner ads and offer-walls become very very useful for you after millions of installs. My only and the strongest suggestion is be a businessman and understand what a business is.
Personal Suggestion, StartApp. I used many ad networks and probably l like StartApp alot, it is not very intrusive like push ads and it pays for per install and they pay in the beginning in the month without any problem, still a bit intrusive but you can use them time to time in your growth of application empire, one day you will not need them, but till that date come, you should check out about StartApp and make series money for you expenses. Moreover, if you use my referral link you will get $25 bonus after 100 install and you will be helping me to improve MTX by covering its expenses.
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