Yeah the Smok app thing is a big mess.
It has to be a Bluetooth 4.0 LE device to function. For Apple devices, you need iOS 6 or later. Then for iPad it needs to be an iPad 3rd generation or newer, and for iPhone it needs to be an iPhone 4S or newer. On Android, it needs to be running Android 4.3 or newer (and have a Bluetooth 4 chip, which will vary by manufacturer but most/all Samsungs do have them, although older Samsungs aren't officially supplied with Android 4.3 or later.)
There's no chance of it working on the Mac, unless they've released a Mac Store app I've not heard of? Don't think so though. I think it's smart phones/tablets only and Macs can't run iPhone/iPad apps.
I ended up having to install Android in a virtual machine on my PC, using a USB Bluetooth 4 adapter, to get it to work! Which actually turned out to be pretty cool, much nicer than using it on a phone
But not exactly a method suitable for the masses.
Anyway, as you have found running Titanium coils on Ni mode will always work and a 100°F offset sounds reasonable, although I would have expected it to be a slightly bigger offset. 80-100°F is the standard on the DNA 40, which has implemented Ni200's exact curve. Other devices, like Yihi chips and DNA 40 clones usually need a slightly bigger offset, maybe up to 150°F. For Titanium coils on devices without a TCR adjustment, I tend to set my TC to 140°C - 150°C which is 285°F - 302°F.
That said, I have found that even with the right TCR set on the Smok, I still have the temp higher than I would expect - eg 250-260°C (480-500°F), so if that's true across the board it would make sense that only a 100°F offset is working fine for you.
It's pretty ridiculous of Smok to ask people to pay $0.45 to allow the moving of a slider lower than 0.04. Doubly so because the only way to activate it is via an app that won't run on a significant number of devices.
Major fail which I expect - or at least hope - they plan to reverse. They did at least enable TC out of the box - originally that required use of the app, and a $2.99 payment, as well. Utterly mad.
Anyway, as you have found there's really no greatly compelling reason to enable the Ti mode. It's nice to be able to set the temp one actually wants, but far from essential - and besides, in the case of the Smok it currently seems like accurate setting is not always possible anyway.
What would have made TCR setting more compelling is if they enabled it to work down to 0.001, which would have allowed accurate Stainless Steel usage. But they stop at 0.0015. That might still be worthwhile, enabling Stainless Steel with a temp offset, though SS is close to the limits of TC even with the right TCR so it's not going to be ideal.
