In This Posting, I wrote that I had ordered NFC Tags from a seller in Australia, just to assure the maximum compatibility with the Android Apps named “NFC Tools” and “NFC Tasks”. Also, this exact brand of Tags (“Whiztags”) seems to have a high number of bytes stored, as far as domestically-used Tags go.
Just as a recap, I should say that Tags can store a small amount of data, which can be read by our device as we use the NFC scanning capability that must first exist in hardware. And this can be similar to how QR Codes can be used. Even though NFC Tags can easily store a small message, in practice we are more likely to store a URL, which when read back in, causes content to display which is visible openly on the Internet. Or, we can also store commands, which our own devices are supposed to carry out, when we tap our device on the Tag.
In the latter case, which I was hoping to start using eventually, it is important that the App which carries out the stored commands, in my case NFC Tasks, be 100% compatible with the App that was used to store those, in my case NFC Tools, as there is no worldwide standard for how commands or automated sequences of tasks, are to be stored. URLs, obviously, at least conform to such a standard.
Well my Tags just arrived in the mail for me. Nobody said that the shipment from Australia was supposed to be extremely fast, and in fact I believe that having purchased these at an extremely good price, pretty much ruled out that they would get shipped to me fast as well.
So now I can start experimenting with programming physically existent Tags, hopefully in a way that will make my use of my phone more practical.
I have to admit though, that before my Tags arrived, I had already started using the App named “Tasker”, along with some of its plugins, to automate and accelerate certain uses I have for my phone, without requiring any NFC Tags per se. Tasker tasks can be triggered just by tapping on an icon, or in my case, when the phone detects that it is charging wirelessly, or when I plug in my headphones…
Yet, there is a limit to how many icons I would want to have taking up space on the limited screen-space of my phone, so that I could conceivably still fine-tune what I want to use the phone for, by preparing several actual Tags, to do what Tasker can also do more or less.
One severe limitation to using NFC Tags however, is the standard fact, that the phone must be unlocked, before the Tag is tapped, before tapping the Tag can cause our phones to do anything. This is just common sense to protect the users. For example, if our phone is set up to make a card payment, by way of NFC, we would also want to make sure that not just anybody can initiate such a financial transaction, without having to unlock a locked phone first.
Well these Tags, by way of the App I installed, can tell my phone to change its settings and do various things which could undermine my security, if I had not programmed them themselves. So just as with the electronic payment card, there needs to be some sort of safeguard in place.
The NFC Tasks App offers an additional safeguard, in that its user can choose to enforce a whitelist, of tags that are authorized to give commands. I intend to use the whitelist feature as well, just so that no hypothetical interloper slips in a tag which I would not have programmed myself…
Also, there is another observation which I should add. The way the use of these Tags is popularly described, we should tap them with our phones. This would suggest that the Tags, which have an adhesive back, should be attached to a hard surface of some kind, because directly from the seller, they come as soft, thin pieces of plastic, which should not even be bent. It would also imply, that an accelerometer in the phone detects a physical tap, to trigger some NFC-realted service to start scanning for the Tag, which has no internal power source of its own.
These tags have arrived with a key-chain pendant, as advertized,
that can act as a semi-hard backing, should I in fact attach one of the tags to this key-chain. I have discovered that the key-chain ornament is itself a tag of equal capacity, which can be verified by just approaching it to the phone while the app is waiting to read tags. Its stats will be displayed just as those of the softer tags. Because of that, It would be a critical error to attach another tag to the key-chain. If one did so, this would superpose two tags, and possibly make both unusable.
But the description of having to tap an NFC-related object physically, has been in error in the past. When I use my phone to make a payment for example, I only need to hold the phone in the vicinity of the store card reader, not tap it.
I have not yet been convinced, that the accelerometer in my phone triggers its NFC coil in practice. It could just as easily be, that the vicinity of one of my Tags will trigger the phone, or else – that the phone might fail to trigger for some unknown reason. If the last thing happens, I will need to troubleshoot.
(Edit : ) The “Whiztags” which I have received, store up to 924 Bytes each, in pages of 4 bytes, and were sold to me as “A package of 10, plus one bonus tag”. This essentially means that I received 11 tags for the price of 11, including the key-chain pendant. They are color-coded for easy recognition, and the one which I have just now programmed, received 120 Bytes worth of tasks from me, which are allocated as 30 pages.
The softer tags have a very thin 3M-labelled backing, which should be peeled off gently, even though the backing itself adheres strongly, to reveal a clean adhesive surface, with which they can be attached to a clean hard object.
The key-chain that was included in my deal,
serves as a possible place to attach one tag in this way. (No! See above comment!)
As I suspected, a strong touching motion or impact between the tag and the phone is neither required nor desired. It is only preferable to know where the NFC coil is located on our phone, in order for the tag to be recognized and processed – within a fraction of a second. On a Samsung Galaxy S6 Phone, this sweet spot is in the middle, of the top half of the phone.
Once a tag approaches there, it is processed exactly as advertized – in my young experience. By now I have also learned: Sometimes, if an operation on a tag seems to be taking too long, the app is actually waiting for the detected tag to be distanced, which the user may still be holding to the device from a prior operation. And then, if the tag is approached anew, the requested operation only takes a fraction of a second again.