What is the best alternative to NeuroNation - Brain Training on iPhone?

memoryOS: Memory Games, S tier, #1 in memory training.

Is there a free alternative to NeuroNation - Brain Training?

Yes: memoryOS: Memory Games (S tier, #1) is free to download, with in-app purchases.

Yes. 1 app ranks above it in memory training: memoryOS: Memory Games (#1).

NeuroNation - Brain Training is S tier, #2 of 6 in memory training. Here is everything that competes with it on iPhone, in tier order.

1
memoryOS: Memory GamesS
Free + IAP · ★ 4.9 · 16,849 ratings · score 95
Memory training app with bite-sized lessons and a 3D game of Virtual Mind Palaces for learning and retaining.
3
BrainHQA
Free + IAP · ★ 4.6 · 21,963 ratings · score 89
Brain training app with adaptive exercises for memory, attention, processing speed and perception, from Posit Science.
4
Train Your Brain: Memory GamesA
Free + IAP · ★ 4.6 · 5,804 ratings · score 89
Free memory training app with card pair, sequence, path and pattern games across multiple levels, with score tracking.
5
Memorize By HeartC
Free download · ★ 4.8 · 2,454 ratings · score 67
Memory training app that helps users memorize speeches, poems, scripts, lyrics and study material through practice.
6
Brain Puzzle Games for AdultsC
Free + IAP · ★ 4.3 · 17,627 ratings · score 60
Daily brain games that test short-term memory and give a brain age estimate without showing an exact age.

What is the best alternative to NeuroNation - Brain Training on iPhone?: memoryOS: Memory Games, S tier, #1 in memory training.
Is there a free alternative to NeuroNation - Brain Training?: Yes: memoryOS: Memory Games (S tier, #1) is free to download, with in-app purchases.
Does anything rank above NeuroNation - Brain Training?: Yes. 1 app ranks above it in memory training: memoryOS: Memory Games (#1).