so it is much more suitable for hand-held operation.
Improvements in power supply and mechanical structure, it can run on USB or a single cell 3.7V Li-ion battery.
Can be connected with computer for data transmission.
DSO138mini has improvements in firmware, too. 
Its trigger can work reliably under 10us and 20us timebase settings.
With Auto/Normal/Single trigger modes, easy to capture the moment waveform.
Available rising or falling edge trigger.
Observable previous trigger waveform (negative delay).
Can freeze at any time waveform display (HOLD function).
Waveform storage function: will not lose the waveform after power off.
Short-circuit and open-circuit detection: can help the user find out the soldering error.
TFT controller recognition function.
All SMD parts has been soldered and the MCU has been programmed.

Note:
The SMD parts in this DIY kit has been soldered, you just need to solder other parts by yourself. 

Specifications:
Number of Channel: 1
Analog Bandwidth: 0-200KHz
Sensitivity Range: 10mV/Div - 5V/Div
Sensitivity Error: <5%
Maximum Input Voltage: 50Vpk (1X probe)
Input Impedance: 1M ohms/20pF
Resolution: 12 bits
Record Length: 1024 points
Coupling Modes: DC / AC / GND  
Maximum Real-time Sampling Rate: 1MSa/s
Time Base Range: 10us/Div - 500s/Div 
Trigger Modes: Auto, Normal, and Single
Trigger Position: Center of Buffer
Display: 2.4" Color TFT LCD with 320*240 Resolution
Supply Voltage: DC 3.5V - 5V
Current Consumption: ~120mA @ 5V
Main Board Size: 70 * 53mm / 2.75 * 2.1in
Analog Board Size: 80 * 70mm / 3.15 * 2.75in
Package Size: 11 * 9 * 2.3cm / 4.33 * 3.54 * 0.9in
Package Weight: 89g / 3.14oz

Package List:
1 * DSO138mini DIY Kit
1 * Users Manual (English)