The truth is, 5E doesn't really need electronic support. That's one of the reasons I like it so much.
For just about anything you might want to do in 5E, the formula is "stat bonus + proficiency (if applicable) + magic item (if applicable)". Since those numbers will tend to range from -1 to +6 at the wildest, this is not something that requires a lot of fiddling or tracking. Spell slots or other character pools (e.g. the monk's ki points) are a little more tricky, but even they are relatively flat.
The one place I can see electronic calculation being handy is in the creation of custom monsters. The DMG has formulae for determining the CR of a critter based on comparing its damage output vs. its defenses, but the calculation doesn't really work the other way around– i.e., you can't really say "I want a CR 4 monster" and get back the desired values, the formula is too dynamic for that. The best you can do is start with an educated guess and then tweak to fit. On the other hand, reskinning monsters is so trivial and "baked in" to 5E, that I'm not sure I'll ever need to create a foe from scratch.
But again, CR in 5E is not the arch-statistic it was in 3.x and up. A group working with a good plan and hot dice can absolutely devastate opponents at a much higher CR than expected. Instead of being the target number for generating encounters, CR is now a signpost of potential threat for the DM. So far in my Silver Coast campaign I've been eyeballing all of the encounters, and even the ones I was worried about have been perfectly manageable.
There are a lot of mathy subsystems in the DMG, such as treasure generation, downtime activities and living expenses, etc., and I can see a "campaign manager" program being useful, but a lot of these have already been put out by fans. So if Hero Lab does add 5E support, I'll certainly give it a look, but honestly, I have a hard time imagining it'll be worth the effort.