Then there are other types of commands, which we can define as “standard”, because they use the NDEF format (NFC Data Exchange Format), defined by the NFC Forum specifically for the programming of NFC tags. To read and run these types of commands on a smartphone, in general, no apps are installed on your phone. The iPhone exceptions. The commands defined as “standard” are the following:
open a web page, or a link in general
open the Facebook app
send emails or SMS
start a phone call
simple text
save a V-Card contact (even if it is not a universal standard)
start an application (only applies to Android and Windows, made with the relative operating system)
Given the transversal nature of these applications, they are often used for marketing purposes.

Compared to UHF RFID tags, NFC tags also have the advantage that you can easily read them by a cheap phone and write them by yourself with a free application (Android, iOS, BlackBerry or Windows).
To read an NFC Tag no App is required (except for some iPhone models): you just need that the NFC sensor is activated (generally, it is active by default as it is irrelevant for battery consumption).