Although Apple chargers are generally the best quality for charging Apple phones, there are generic versions available as well as aftermarket companies that specialize in mobile accessories. These chargers can be purchased from electronic retail stores and websites.
Large department stores, such as Wal-Mart, have their own in-house brands. ONN is Wal-Mart's own brand that retails low-cost alternatives to mobile accessories. The price difference between an in-house brand and name brand can be more than twice the cost.
Aftermarket companies also produce high-end car chargers that work with the iPhone. Some chargers offer options such as solar charging. The PowerMonkey Solar Charger is one example that allows a user to use sunlight to charge their phone.