Identifying component from i2c trace & obscure SMD marking
This is a Bosch accelerometer, likely the BMA223 or a variant. Key points:


Recommended land pattern has four traces coming out on each of two opposite sides (and two traces on each of the remaining sides).
Packaging marking for the BMA223 is XXX/•MX where X are internal codes. (The M is the only thing I noticed distinguishing this from other Bosch accelerometers.)
0x18 is the default address for the BMA223.
The 0x3F register is the FIFO_DATA register, which can be read in a burst to read the contents of the FIFO.
The first write to 0x18 in your trace is to 0x14, with value 0xB6, which is the software reset command for this chip.