The .APP new gTLD has passed the 150,000 domain name registrations just after a few days it entered its "GA" period.
The General Availability period
Known as "GA", this period is when a registry has ended all previous periods such as the Sunrise Period one, Landrush and/or other EAP periods (for Early Access Program).
The GA period is the most important one for a registry dedicated to selling domain names through the network of accredited registrar. It allows to see if the business model chosen to launch the extension was good or not. When registrants buy lots of domain names on the first days of GA, it can mean that the extension will meet adoption.
A little history
In the case of the .APP new gTLD, there is an historic background since the owner of the Registry is "Google" and the application was won in an auction for $25,001,000.00. These are the two first main reasons why the launching of this extension was followed by various parties.
Another reason is that it is short and memorable for application developers who will want to demonstrate precision when introducing their "app" on a website. Amazon offers the same kind of extensions for Bot developers with a .BOT new gTLD.
Also, the number of mobile-only Internet users now exceeds desktop-only in the U.S and what do you need on your mobile: apps.
The .APP Business model
The business model chosen here was to sell these domain names at an average price below $18 (more or less) at retail registrars like Uniregistry or Google Domains, with a renewal price close to $25 each year. It is important to note that a SSL certificate is mandatory to use a ".app" domain name.
With the SSL certificate, understand that the price of the certificate should be added to the price of the domain name and hosting...unless if you decide to use G Suite where the SSL certificate is "offered" when using the latest version of Google Sites.
I am no application developer so I don't really need such domain names and I find that the price is a little high compared to other domain name extensions, I like the idea to force users to use a SSL certificate: with the general increase of online fraud, it makes sense to show a secure website introducing an application. Will application developers use a ".app" domain name? I think so because Google has a strong image and an impact on users.
I also just think that it makes sense for a company to introduce its application(s) using a ".app" domain name...because "app" is the word commonly used and understood for "application".