Sometimes, I wish everyone had an iPhone. If they did, then people could communicate with each other using iMessage (or other options like WhatsApp Messenger).
However, many people use Android, Windows Phone, or even plain-old feature phones, which means that for now at least, you're stuck using old-school SMS (short message service) if you want to be able to send text messages to everyone. So what options are there for using SMS with your iPhone?
1. Just use the built-in iPhone + AT&T SMS capability This is the most obvious option. SMS capability is already built into iOS, and if you use the built-in SMS functionality, you get to keep your own phone number and you don't have to install any software. Some people think it's unfair that phone companies profit so greatly off of SMS plans when SMS places such a small burden on their network - but come on, text messaging is valuable to you, right? So if it gives you the ability to keep in touch with all your contacts, I think it's perfectly reasonable for AT&T to tack on an extra $5/month for its unlimited texting plan.
What, WHAT? The unlimited texting plan costs $20/month!?
2. TextPlus The alternative is to install an app. All the SMS apps have pretty much the same basics: they assign you a separate phone number for texting, and instead of using the built-in iOS SMS functionality, you use the app. Apps are generally ad-supported, and they can send text messages to anyone with SMS - feature phones, other iPhones, even your own iPhone phone number. The apps are free, but they offer additional features through In-App Purchases. You can also receive SMS alerts, and the apps will send you push notifications if one comes in while the app isn't active.
TextPlus is one such app, and it happens to be a beautiful, slick looking app. The simple, elegant interface will get you up and running with your secondary text number in no time, and the company's support and friendly and easy to get ahold of. SMS is free, but it also has a VOIP service you can buy for an additional cost.
There's really only one problem with this app: it doesn't work. You constantly have to refresh the screen to try to find new messages, and if you get a push notification and tap on it to try to reply, somehow the Send button within the app just stops working. The bugs are so pervasive that, sadly, the app is just not usable. Sigh.
Editor's note: Subsequent to the posting of this blog, an update to TextPlus was released on 7/29. At this time we have not had ample opportunity to test if the bugs mentioned have been fixed.
3. Text Free Pretty much the same model as TextPlus: install an app, get a secondary number, send/receive SMS for free, pay extra if you want to use VOIP.
Text Free is much more stable and usable and TextPlus, but sadly it has a fatal flaw of its own. It's understandable that a free service would be ad-supported, but this app has enormous ads that pop up constantly and overwhelm the interface. You do have the option of using an in-app purchase to remove the ads, but even if you buy that, the app itself sends you a text message nearly once a day with "Tips of the Day." These "tips" are very annoying and not very informative, and you can't turn them off.
4. TextMe 2 TextMe is the only app out of all of these that picked a secondary number that was actually within my local area code. It also offers the ability to remove ads via an in-app purchase as well as other minor niceties such as custom wallpaper.
TextMe just works. It has all the "usual features" like pay-for-VOIP, and SMSs get through quickly and reliably. It doesn't have any "killer app" feature, but it also doesn't have any fatal flaw.
The Winner Is...
TextMe, of course. I wish I could say that TextMe wins because it offers clever and innovative new features, rather than saying that TextPlus wins because the competition is broken, but nonetheless TextMe is a solid app, and if you are looking for a reliable and inexpensive way to use SMS, TextMe is my recommendation from the current bunch.