Temporary Ad Version
One of the most popular models used by developers is to offer a lite or partial version of a game or application. This attracts attention from iPhone users, who can download these apps and try them out. These lite versions are often linked to the full versions of the applications, allowing developers to more effectively market their offerings. If a user likes the lite version of a game or app, he can pay for the full version. This distribution method allows users to avoid wasting money on premium applications that have few features.
If you download a free iPhone application or game, you will often notice a link to the paid version inside. If you click this link, you will be taken to the App Store right on your iPhone. This is the easiest way to upgrade a free application to a premium version. Another way to do this is to plug your iPhone into your computer, log on to the iTunes app store, and purchase the full version. Once it is purchased, you can sync it to your iPhone. Wi-Fi is your best option for downloading full versions of games and apps, as you may be restricted from downloading large files through a 3G network.
If you are thinking about upgrading from a free app to a full version, you need to determine if it is worth the cost. The most obvious difference between free and paid versions is ad support. Free iPhone games often have banner ads, especially if they are lite versions of a game. The free version may even be a full version of the game with ad support included. The newer PlayMesh classics series does this concretely, especially with games like Link4, Tic Tac Toe Online, and Roshambo Online. They were popularized by offering free PlayMesh Points for RPGs that were popular at the time, yet now the free PlayMesh Point offer mechanism has become less useful since many of those titles have fallen away. These games all have pay versions that are several dollars each, while the free versions are the exact same thing with ad support. This is the financial alternative for PlayMesh Points, where they normally make their money through in game purchases. If you can get the same game for free, and don't mind banner ads, it's not worth it to upgrade to the premium version. If the free version has fewer features or limits the number of levels you can play, it may be worth upgrading to the full version.
Some apps allow you to upgrade in sections. This means that the free version is a basic element of the game. If you want to upgrade, you have to pay to add to the game. For example, the free iPhone game Ramp Champ asks you to upgrade by adding new levels to the game. This allows you to decide exactly what you want, and helps you avoid spending money on game elements that are of no interest to you. This is going to become altered as more games become tied into the growing Game Center and now that the iOS 5 is on its way the expectations for gaming upgrades will change further.