Because it's not secure. Someone else can port it out from under you.
As I indicated in the Visible thread, I placed a swap order for a Moto G and gave Visible port-in information for a number I currently have with TextNow. In giving that info to Visible, I never contacted TextNow to find out what my port-in acct number and PIN are. Instead, I just deduced some information based on my experience porting out a previous number I had with TextNow.
I apparently deduced correctly that TextNow uses certain defaults. Today, I got this email from Visible: "...good news: Your old phone company has approved release of your number 201-xxx-xxxx to Visible!
--If someone gets information from another source that your number is with TextNow, they will know the account number.
--As for the PIN, it seems that it's the same for every account in TextNow's system. It's similar to how Visible initially had their PINs set up - it used to be '1212' across the board.
I parked a number with google voice going on over 5 years now. No issues. Except for the fact that other company's see this now as a google voice number rather then the original sprint. So I took a real number and turned it into a throw away number.
It depends on what your application is for Google Voice & TextNow. Both offer free VoIP calling over WiFi (or other data source). Both offer a nearly free place to 'park' a number.
Google Voice has a call-redirect feature: this is my primary use for GV, so that my number stays consistent no matter which phone I'm using. TextNow doesn't offer this.
TextNow, with the SIM, provides a portable cellular data source for VoIP calls. Google Voice doesn't offer this.
So on TextNow's end, I got the following email from them last night:
"We were informed that your TextNow phone number has been ported out to another carrier. To ensure that there are no issues with the number on your new carrier, we have removed it from your TextNow account. If you would like to continue using our service, please sign in to your TextNow account and you will be assigned another number."
Just to re-emphasize, I managed to do this without ever contacting TextNow for my acct # and PIN, and you can't get port-out info from TextNow's online interface after you log it ala Tello
So if you hadn't figured it out on your own what would obtaining the port out info. on free account have entailed (if even possible)?
Do you think it would be possible to change PIN on free plan?
Sounds like if you don't care about the # & security of it you can have an "eternal fountain" of free #'s via TextNow.