GreenM, the thing to remember about the forum-based guide is that it's quite truncated when compared against
the unabridged guide, which tends to answer more questions, provides links to various terms and topics, and even covers hardware shopping for services. Unfortunately due to the limitations of the forum software here, it's just simply impossible to include it all here and still leave it coherent.
Also, for what it's worth, there's also a stickied comments thread for the guide
here, and I'm less prone to miss these sorts of questions on the forum if they're there. Subject lines help a lot, which is why I noticed yours, but it's still no guarantee these days given how fast the forums are moving.
Regarding your needs specifically, it's obvious that there's room for improvement, but we need to address the phone first, and explain the notification you received.
The Service Discontinuation Message & What it Means for YouWe'll start with the current phones. You didn't mention what the model number was on these handsets, but I suspect they date to 2008 or earlier in age, which means they're 2G GSM handsets. AT&T is twilighting their 2G GSM network at the end of this year, and anyone that doesn't have a 3G GSM handset or newer (including 4G LTE) for use with an AT&T SIM will lose service. Clearly, this impacts all AT&T network users, whether you're on AT&T postpaid, GoPhone, Cricket, or any AT&T based MVNO.
Handset Shopping, Recommendations & AvailabilityAs for your current situation, it's clear that you need to stick with a basic, rugged feature phones. You'll get better battery life, better reliability, better tolerance to less desirable environmental conditions, you get the idea. It'll be cheaper, too. Regarding features, clearly you'll need to use 3G GSM (UMTS/WCDMA 2/5 or 850/1900MHz band) handsets if you intend to stick with AT&T coverage moving forward, and I see no reason for you not to given your situation.
It sounds like you've had reasonable luck with clamshell (flip) phones in the past, and if it works for you, stick with it. Candybar handsets can frequently be more rugged under most situations (solid, no moving parts), but depending on how dusty the environment is and how scratched up plastic can get, not having the screen protected can cause longer term problems. On that subject, you mentioned the possibility of a camera. It's pretty common issue on even the cheapest of feature phones these days, but they always leave the lens exposed, and it tends to get scratched up if not well protected. I bring this up given your apparent usage pattern and the possibility of sticking with a clamshell to protect against scratching. If scratching has been an issue with the plastics on the old phones over the years, don't expect the ability to take anything but foggy pictures with a newer phone in the longer term.
When shopping for a replacement phone, it's usually wise to stick with what's worked for you. I suspect you've used these Samsung clamshells for at least eight years (if not longer) by this point, so it might not hurt to keep doing so. Nothing against Nokia feature phones (when/if you can still find them) as they're great, too, but there might be a better chance of UI familiarity and muscle memory carry-over by sticking with the same manufacturer. With this in mind, it becomes a bit easier to narrow a list down, which makes using tools like
PhoneScoop's search tool easier to use.
Samsung. 3G GSM handsets. Flip/clamshell. Congratulations, you now have ten options to look for and price!
The Samsung Rugby series handsets are some of the tougher, but there's a high demand for the things in the used market, so they tend to fetch a premium. On that list, one of the most current and prolific is the
Samsung A157, as lots of AT&T branded GoPhones have been sold of that model, and a lot of AT&T MVNOs who sell handsets usually have this phone in stock as well for around the $15-25 mark. Unfortuately, they're not currently being sold new through GoPhone brick and mortar locations. So, this addresses an ideal, but not a quick fix.
Before going further, a note on GoPhones: even carrier locked, GoPhones can technically work with any AT&T MVNOs without carrier unlocking, but data and MMS can't be changed on them. The legal requirements to unlock them are six months of service on a GoPhone account, and technically the prices when sold are "subsidized". Long story short, you can use the phones elsewhere out of the package, but not without violating some ethical and legal barriers in doing so.
Currently, GoPhone is only selling the
ZTE Z222 handset, which Khaetra mentioned, and they sell for $15 new down at Walmart - though they appear to be on clearance and will eventually be replaced with the
LG B470, which AT&T is selling for $50 currently on their website (not many outfits are making feature phones anymore, sadly - and some of the best ones that are still trying to innovate aren't producing 3G handsets *cough
BLUcough*). I'm personally not a big fan of ZTE's firmware and build quality, but if it works for you, fantastic! If you plan on sticking with GoPhone for a bit longer and want to carrier unlock or use a stop-gap until you can better optimize (or even if you like it), this might be an easy and quick fix that can be resolved with a trip down to a local dollar store or Walmart today and just pulling your old SIM card and stuffing it in the new handset. Just be sure to save your contact list to your SIM card in your old phone first so you don't have to manually transfer contacts and can just import the contacts from the SIM card on the new one.
For a good overview on potentially shopping for used handsets,
this post covers it fairly well.
That should cover you on hardware.
Future Plan OptimizationI know you're only using about two hours of talk time each month between the two lines, but there's a couple points worth mentioning. 1) You're grandfathered in on a much older PAYGO plan, and AT&T's newer PAYGO plans are $2/day unlimited talk and text or an even more outrageous 25¢/minute and 20¢/SMS. 2) If you transfer service and your phone line to a new SIM card with AT&T GoPhone, you will lose your current rates - this is why I highly recommend you migrate your old SIM cards if at all possible on the short term end. However, if the phone is thoroughly trashed, SIM included... you should know what's in store for you if you transfer service to a new handset and SIM card from them. Staying put can potentially get real expensive, real fast.
As an alternative and knowing what you're currently paying, there's the opportunity to potentially halve your monthly costs by switching to
H2O Wireless. Same AT&T network coverage, but only 5¢/minute/SMS and 10¢/MMS. Minimum $10 refill good for 90 days, balance rollover, and a discount option for auto-refill. $3 will basically buy you an hour of talk time, which is coincidentally around the same minimum aggregate monthly cost to keep the account alive. With that in mind, it wouldn't hurt to bank a month or two of standard level usage as overkill up front to buffer in case of unexpected heavy usage at any point... so maybe start out with a $20 credit and then switch over to the $10 refills. Their customer service quality isn't as good as Airvoice, but Airvoice's PAYGO rates aren't near as good unless you're using their $10/month plan... and that'd be overkill for you. I might also add that H2O isn't selling any flip phones currently, and their feature phone selection is all ZTE and Alcatel. You'd probably be better served shopping used/refurb and carrier unlocked for a phone more in line with known good expectations, such as with the Samsungs above or possibly a Nokia 6350.
I reckon that should give you plenty to work with. Any other questions, don't hesitate to ask!