First-generation Apple iPhone will become officially obsolete at Apple's retail stores on June 11th
vintage. These are products discontinued more than 5 years ago, but less than 7. Such devices receive no hardware support except for those units bought in California where repair coverage is mandated by law.
Despite the obsolete status of the OG Apple iPhone starting on June 11th, as far as AppleCare and Authorized Service Providers are concerned, the device will be considered vintage which means a well placed call ahead of time might still be able to get you some service on your ancient model.