Help building icons and splash pages for Android (hybrid) and iOS app

I’m having a difficult time aggregating the proper information about building all the necessary Android icons and splash pages (and I’ll want iOS next, ideally even Blackberry).

This thread looked promising but it seems that the discussed package (buildhybrid/assets) has been not working since Meteor 1.1.0.1, and apparently abandoned, in April: Let's auto-generate mobile-config.js & resources for Cordova

I’m still putting some faith in this SO thread from 2015-11-14: https://stackoverflow.com/questions/26957503/meteor-way-to-specify-icon-and-launch-screen-of-an-app

Naturally I’ve read http://docs.meteor.com/#/full/mobileconfigjs which seems to concur with the previously mentioned SO thread, but looking for tools and considering free images that I might use as a starting point has been tedious and not at all confidence-inspiring.

Some links that I’m still trying to weigh are (just to name a couple):
http://ticons.fokkezb.nl/
https://romannurik.github.io/AndroidAssetStudio/icons-launcher.html#foreground.type=image&foreground.space.trim=1&foreground.space.pad=-0.1&foreColor=607d8b%2C0&crop=1&backgroundShape=square&backColor=ffffff%2C100&effects=none

I’m a developer and I’m not needing professional design perfection at this pre-alpha stage. I’m really just wanting 2 things:

  1. Authoritative list of what sizes I need (should I go by the SO link above)?
  2. Hopefully some recommended tools so that I don’t have to rely on my limited Gimp or Photoshop skills.