No shame in upgrading if you are having issues that can't be cheaply fixed, or if you would prefer the upgrades that have taken place in the four recent generations.
One option is to find a 5 or 5s either new or as a resale online to reduce the cost, or maybe wait until the 6s is coming up and then getting the current 6 for a bit of a discount (likely in around 6 months).
I've got a 5 currently since early 2013, and really wanted to upgrade but decided against it since I cirrently have no issues with the handset. In the future, one way to reduce overall handset costs is to sell your device while it's still functional and 2 generstions prior on eBay since you can get a bit higher net price after fees than recycling to Apple. Then, buy the recent generation new.
As a current example, you can sell the 4s for roughly 100, and buy a new 5s for 550. roughly 450 every two years suggests a monthly handset cost of ~19 per month. This compares to a standard new phone every two years of 650/24 or ~27 per month. Alternatively, you could increase that upgrade cycle to 3 years, but your resale value will decrease. Let's estimate 50 resale for a 4s and buy a new 6. Net cost of 600/36 or ~17 per month.
Cricket wireless I believe is 35 per month service plus 650/24 for a new upgrade every two years paid in full 27/month) less the resale value of ~200 for a 2 yr old device so reduced by 8/mo. All in wireless costs of ~55/month with a constant device of 2 years seems to be fairly frugal.
Anyway, a few options to consider depending on your feature preferences and each will save you money if you go with a cheaper service reseller compared to att or Verizon.
