Using External SD to extended Internal Storage – MLC vs TLC MicroSD Card

Fundamentally, SLC is 1-bit per memory cell, MLC is 2-bits per cell, TLC is 3-bits per cell.
As bits stored per cell goes up, reliability drops.
As the chip structure shrinks (nanometer), reliability drops.

Users of the F6, or any cellphone, using the MicroSD card as an extension to limited internal storage space (eg. App2SD) will want to consider using SLC or MLC microSD cards instead of the cheaper TLC cards due to reliability issues. Simply opening and closing a complex app or game can result in hundreds of write cycles to a MicroSD card.

With SLC cards, each cell can withstand 100,000 write cycles or so; MLC, 3,000 or so; TLC, a mere 500-1,000 cycles!

Users can easily exceed 1,000 write cycles within a year of using a TLC MicroSD card, and suddenly find their MicroSD cards have failed – losing photos, data and more.

As a price comparison as of 1/2015, the Panasonic 32GB MicroSD card MLC RP-SMGA32GAK is $35.
Cheapest 32GB MicroSD cards hover around the $10-15 range, or about a $20 difference.
Currently, SLC cards are limited to smaller capacities (<=16GB, and typically for industrial use as they are pricey.)

THUS, users who use TLC cards and suddenly find their App2SD or other method of using the external MicroSD card as internal storage failing on them may very well be experiencing this problem.
Be smart! If it’s important and you don’t want things failing on you sooner than later, buy and use a SLC/MLC MicroSD card!

Barun Electronic’s Gold Flash PLUS (32GB) TLC
Barun Electronic’s Gold Flash PRO (64GB) MLC
Memorette (memento) Expert (64GB) TLC
Memorette (memento) Standard premium (8GB) MLC
Lexar High-Performance UHS-I cards [300x] (64GB) TLC MLC [LSDMI64GBBNL300A]
Kingston Advanced Class 10 UHS-I (64GB) [Also Known As Kingston UltimateX MicroSD] TLC [SDCX10]
Transcend Premium UHS-I [300x] (64GB) TLC [TS64GUSDU1E]
OEM microSD by Samsung (64GB) TLC
For Samsung UHS-I Class 10 (32GB) TLC
Samsung Plus (64GB) TLC [MB-MPCGCA]
Samsung EVO (64GB) TLC [MB-MP64DA]
SanDisk Ultra UHS-I [Old series] (64GB) TLC [SDSDQUA-064G]
SanDisk Ultra UHS-I [2014 Model] (64GB) TLC [SDSDQUAN-064G]
Lexar High-Performance UHS-I 633x MicroSD (64GB) MLC [LSDMI64GBBNL633R]
Kingston CL10 UHS-I 90R/45W MicroSD (64GB) TLC [SDCA10]
Samsung PRO [Old Series] (64GB) TLC [MB-MGCGBA]
Samsung PRO [New 2014 Series] (64GB) MLC [MB-MG64DA]
Sony High-Speed R95 UHS-3 (64GB) MLC [SR64UXA]
PNY Turbo Performance High Speed MicroSD (64GB) MLC [P-SDUX64U190-GE]
SanDisk Extreme microSDXC UHS-3/U3 [2014 Edition] (64GB) TLC [SDSDQXN-064G]
SanDisk Extreme Plus microSDXC UHS-I [2014 Edition] (64GB) TLC [SDSDQX-064G]
Fake SanDisk Ultra UHS-I (64GB 8GB) ??
SanDisk Standard Class 4 (32GB) TLC