There are two types of in game currency, coins and Meteor Credits.
In this wikipedia, coins are simply shortened to c. For example, 1,250 c.
All players start out with 200 c. No coins are awarded for gaining a new level.
How to obtain them
Plowing, seeding then harvesting is the primary method of obtaining more gold.
Players can cast a net and make a catch.
Salvage may randomly appear on your island or a neighbor's island. They may be collected at no cost to the neighbor.
Stealing from neighbor's crops, trees and animals will let you make off with some of their harvest.
There is a limit to the number of coins a player can have. No (known) person or persons have reached the limit yet, nor have Meteor Games staff disclosed what it is.
Earning coins will unlock achievements. Earning 5,000 coins unlocks Penny Pinching, earning 25,000 coins unlocks Coin Collector, earning 100,000 coins unlocks High Roller, earning 250,000 coins unlocks Money Magnet, and earning 500,000 coins unlocks Half Millionaire, the final coin earning trophy. The count is cumlative, meaning that the first 5,000 coins you earn for Penny Pinching will add to the Coin Collector count and so on.
Not Being credited
Look to this wiki's Common Problems page for help.
Meteor Credits, or MC as it is often shortened to, can be bought with real life money or by completing Super Rewards offers on the +Add Coins and Credits tab above the game window.
When you start playing Island Paradise, you start out with 100MC. You gain 10 Meteor Credits each time you gain a new level. It is also possible to gain Meteor Credits each time you spin the Tiki Wheel. You do not get Meteor Credits for opening Mystery Gift Boxes however, those are experience points.
There are various packages a player can choose from under the +Add Coins and Credits tab, as well as various methods of payment.
Players can purchase cards from Target and redeem them. These cards are currently available in stores in the US only. They only come in $15 denominations currently, giving you 1500MC.
If you can't find them at your local Target store, you may have to ask the people at the desk to search for the item number. The number is "012-15-0444".
You can also "gift" your friends Meteor Credits by purchasing a card, and then either sending the actual card to them or emailing them the code with the instructions. (This will also work to send Meteor Credits to people not in the US.)
It is highly recommended to read the fine print on all offers before completing them and be aware that there may be malware from third party downloads. Offers may take a while to credit, and if they remain uncredited well after a long period of time, it is recommended to use the green View Status button on the offers page and contact Super Rewards to get them. All offers are region based, so depending on where you live, you may see more or less of these offers. Super Rewards is responsible providing all offers, not Meteor Games.
Application of the Day
This offer will allow players to add another Facebook application and gain some Meteor Credits. Usually players gain 11 Meteor Credits. Once you have received the credits, you can delete the application if you don't want it.
Players can complete surveys or sign up with various surveying sites. It is recommended that if you don't want the survey site to spam you to filter them from your email or to have a separate email.
There are other offers players can do to obtain Meteor Credits, including purchasing other items.
Not being credited
If your Meteor Credits are not being credited, look to this wiki's Common Problems page for help.
Little Rock Pool, Ranch Town and My Sweet Shop
The balance of Meteor Credits you have is shared with the other Meteor Games applications, Little Rock Pool, Ranch Town and My Sweet Shop. You have one Facebook account, and this gives you one Meteor Credit balance. Anything done in one application will affect all of them. That means a gain of 100 MC on Island Paradise will result in a gain of 100 MC on all applications and vice versa. Spending 100 MC on Island Paradise will result in a loss of 100 MC on Little Rock Pool, Ranch Town and My Sweet Shop and vice versa.
Adding Little Rock Pool for the first time will give you 100MC. Adding Ranch Town for the first time will also give you 100MC. Adding My Sweet Shop also gives you 100 MC the first time you add it.
Converting Meteor Credits to Coins
Meteor Credits can be converted to coins with the use of the green in game button.
Coins cannot be converted to Meteor Credits.