J
- Jolla (smartphone)
- Jolla C
- Jolla Launcher
- JXD P861
K
- Kenxinda
- Kyocera 6035
- Kyocera Echo
- Kyocera Zio
L
- Lenovo A526
- Lenovo K3 Note
- Lenovo Vibe P1
- Lenovo Vibe Z2 Pro
- LG enV Touch
- LG eXpo
- LG GW620
- LG Intuition
- LG Optimus (original)
- LG Optimus 7
- LG Optimus Chat
- LG Optimus Chic
- LG Optimus L9
- LG Optimus One
- LG Optimus Q
- LG Optimus Vu
- LG Optimus Vu II
- LG Quantum
- LG VS740
- LG Vu 3
- LiMo Foundation
- Mobilinux
- Liquidmorphium Turing Phone
- List of countries by Internet access from smartphones
- List of countries by smartphone penetration
- List of features removed in Windows Phone
- List of smartphones supporting GLONASS navigation
- LuneOS
M
- List of devices using Mediatek SoCs
- MeeGo
- Meizu M1 Note
- Meizu M8
- Meizu M9
- Meizu MX
- Meizu MX2
- Meizu MX3
- Meizu MX4
- Meizu MX5
- Meizu Pro 5
- Mi-Fone (mobile)
- Micromax Canvas 2 A110
- Micromax Canvas 2 Plus A110Q
- Micromax Canvas HD A116
- Micromax Ninja A89
- Microsoft Lumia
- Microsoft Lumia 550
- Microsoft Lumia 650
- Microsoft Lumia 950
- Microsoft Lumia 950 XL
- Mobile phone overuse
- Momentem
- Moments (social networking)
- Moto E (1st generation)
- Moto E (2nd generation)
- Moto G (1st generation)
- Motodext
- Motorola A1000
- Motorola A760
- Motorola A780
- Motorola A910
- Motorola A925
- Motorola Atrix 2
- Motorola Atrix 4G
