Games like N back task(single and dual)

Here are some great alternatives to N back task(single and dual) by NoMi :
Dual N-Back: Brain Training
Dual N-Back: Brain Training
★4.4
Dual N-Back Ultimate
Dual N-Back Ultimate
★5.0
N-Back Evolution
N-Back Evolution
★5.0
Memory Games: Brain Training
Memory Games: Brain Training
★4.2
Complete Memory Training Game
Complete Memory Training Game
★3.3
Brain Training
Brain Training
★4.2
Train your Brain
Train your Brain
★4.4
Smarter - Brain Training Games
Smarter - Brain Training Games
★4.5
N-back Math
N-back Math
★4.2
N-Back Memory Training
N-Back Memory Training
★4.4
NeuroNation - Brain Training
NeuroNation - Brain Training
★4.6
Brain Boost: Focus
Brain Boost: Focus
★4.0
Focus - Train your Brain
Focus - Train your Brain
★4.6
IQ games N-Back Brain Premium
IQ games N-Back Brain Premium
★3.7
Concentration: Memo Attention
Concentration: Memo Attention
★4.6
Mnemocon - Improve memory!
Mnemocon - Improve memory!
★4.2