I have beaten the entire game in the span of an hour. Exactly 100 levels, with roughly 80 or so being unique. For what it’s worth, the ads themselves (for me, results may vary) are rarely the obnoxious 30 second unskippable videos but rather images that you can immediately pass, and only occurred roughly every other level.
That is, unless you fail a level due to inaccurate controls, which is possible due to the game either pitting some pins too close together or due to the game not giving you any control in how far you can actually pull the pin, leaving some levels to pure luck. At best the poor controls (when they manifest) simply have you swiping at the same pin with no result for a fair few seconds.
As mentioned in the title, for a free, ad supported game, there are no micro transactions so that is a bonus given how small it actually is. Also, don’t be fooled by the images in the page; every level is the same bland shade of gray in the background and the white colored structure that makes the level also never changes either.