If you are looking to scratch that Heroes of Might and Magic itch on iOS, you might like Palm Kingdoms 2 (PK2). It's a total knockoff of HoMaM, but a well implemented one, with dozens of interesting map packs. It kept me entertained for about 100 hours. I remember finding it more compelling than the actual port of HoMaM3.
And, while looking this up trying to remember the name of PK2, there appears to be a new offering from the same developer called Royal Bounty Remastered. I haven't tried it yet, but now I'm intrigued. Let me know if you have played it and would recommend or disparage it.
[edit: reading a little more about Royal Bounty, it looks like they may have just taken a few of the best maps/quests from PK2 and repackaged it to try to monetize it differently, so I'll probably skip that one unless I hear rave reviews about it, but I still give PK2 a thumbs up, hoping they haven't tainted it with aggressive marketing -- the latest update mentions something about pop up ads and there were no ads at all when I played through it a year or two ago.]