Title pretty much says it all - I’m all in on getting the Apex Flex the millisecond it’s released, but have also been considering a flexDF2/xDF2. The difference between the flexDF2/xDF2 (other than the obvious) is enhanced range in the flexDF2, as far as I know.
It depends entirely on how you plan to use the xDF2. If you just want to format all 8 kB as an NFC NDEF container, then it’s really not worth it because the apex will allow you to deploy an NDEF applet up to 16k in size.
If you are interested in making software to leverage the features of the xDF2, then it would stand to reason you could use those same skills to develop applications for the Apex. There are specific types of “files” you can define on the desfire that make them conducive for specific applications… But again you could easily develop your own Java card applet that is actually perfect for your application and deploy that to the Apex.
The only thing the desfire chip has that the Apex chip will not have is privacy mode, where the UID is randomized for each ISO14443A session. The Apex cannot do that (as far as I know anyway).
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Waiting for the apex flex now I need an apex ship. Dagnabbit. Running out of flesh
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This is super helpful, thanks @amal! I’ll probably just get the Apex then since it does seem like it’d be redundant for me. Love that the Apex will have so much more storage!
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Maybe I missed something but can anyone help me with the random UIDs per session with any use case examples?
Do you mean like what is the point of randomized UIDs? Basically it’s a privacy feature. Because the desfire chip can essentially lock all content behind standards based encryption keys, the UID is the only thing left that could uniquely identify one chip from another. By enabling privacy mode, you would not have any way to know what chip you were talking to, until you attempted to authenticate that is. So basically it just means that certain applications which have extreme privacy concerns can utilize this mode. I’m thinking something like government or, who knows really. NXP just enabled it as an option and I think it’s kind of cool, even if it’s not used all that often.
Be warned though, once enabled it cannot be turned off.
One potential example comes to mind actually. There was all this talk about NFC passports being used to target specific citizens… like some sort of bomb in a public space is triggered only when a US passport is detected in the vicinity. Similar targeted attacks against specific individuals who carry an ID badge with a specific UID could be possible, for example. I mean maybe not a bomb but something similar or some type of similar targeted attack. Let’s say a building has 20 agents that go through a specific door and you wanted to be able to target a specific one. You couldn’t really use the UID to do that if it’s random for each agent every time they use the door.
So as i understood the apex would be enough.
Because I plan the next implants I asked myself which one or two could be the right ones.
NeXt (done), I can open my door, unlock my pc if I want and maybe clone my work batch, correct?
Apex - I will be interested in if it will be released (hopefully soon 
no pressure 
)
I think about some use case like cloning hotel badges therefore timide maybe another Next or so.
I like the idea of the xM1 if I remember correctly because of the capability of changing UIDs.
Another use case will be storing data like healthdata independent of other implants and will only be used for that.
Happy to brainstorm
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How much health data do you plan on storing?
The company I work for would not be able to import data from a chip, won’t read from USB drives, and has a large EHR system.
Personally I am considering a FlexMN for lf and hf cloning and the Apex flex.
But that is just me.
it depends. I think in the first step not that much. Blood group, age, address, emergency contact and things which is necessary in an accident case.
the xM1 would be for often changing access cards and system. So my assumption is to use it for hotels and the company would be great but also for PC logins if the rules makes it necessary to change the UID often.
For all other things like storing general data, identity use cases etc the Apex will be the way to go AFAIK.
So, would you have a tattoo above it saying “in case of emergency scan here”?
In a true emergency none of that would be relevant. Blood group is usually tested before giving you blood anyway to ensure that they get it right.
I’m not saying don’t do this, but that I am not sure it would be useful.
Storing contact details like a business card would probably be more useful overall.
You‘re partially right. Things like medicine or something or allergy could be important to store.
But I think most important is to habe that separated.
So, I think the xM1 because of randomizing the UID and the apex would be the next ones.
The other thing I think. Does it makes sense to have the xM1 or better a second NeXt.
xM1 has the advantage that you have additional possibilities. Mail use case would be to use it for access systems, hotels and such things. Maybe as I read for terminals like in trains or tubes.
Nice thing is the changeable ID.
Now I’m confused.
What is the difference between the two or better to say why the xDF2 instead of the xM1
I’m sorry haha. You can change the ID of the xM1, so you can randomize it by writing a random ID to it, but the DF2 implants have a feature called privacy mode, where they just show some random ID. DF2 chips dont need an ID, as they can do better authentication mechanisms. You want an xM1 if you have M1 cards to clone. Edit: amal just said that all.
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Got it.
So the question is what is in the hotel, tubes etc.
does the xDF2 makes sense or better the xM1.
I think about login to the pc as well. From what I’ve learned the xM1 would be a good choice if the password have to be changed in a period of time.
Of course the xDF2 has the advantage of big storage.
Yes the xM1 is “the best for hotels”, meaning that you’ll find a lot of hotels, or ticket systems etc with M1 cards I guess.
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That’s was what I learned.
Thanks for support
Another question. If I have the apex or whatever implant to store data. What I recognized so far is that if you read it, you can’t choose what is readable. I mean, if I configure to open a url and store store some data, for every read I get both actions / infos. Correct?
Yes, for typical NFC NDEF. But if you store data on the apex witha special app + applet, you can do what you want.