We present new principles underlying optical trapping and manipulation techniques by introducing an additional degree of freedom: the polarization gradient found in evanescent fields. These evanescent fields are common at the micro and nano-scales. When generated by guided modes in integrated waveguides, these evanescent fields exhibit transverse spin and Belinfante momentum. Both of these properties can be harnessed for optical trapping and micromanipulation. Our technique can be integrated with photonic integrated circuits to leverage their rapid construction and widespread deployment...