pH-responsive Polymer-Based Systems like polymeric micelles, hydrogels, and lipid-based technologies can assist in cancer treatment where drugs are undergoing release only at certain regions within a tumor implant hence augmenting their delivery efficiency. pH-Responsive polymers and lipids can change their structures in response to the pH gradient of solid tumors; this permits stepwise medication delivery within the acidic TME. This review aims to discuss the different categories of pH-sensitive drug delivery systems based on the comparison of its working principle, the recent development of the concept, and the applications. Liposomes and pH-sensitive lipid nanoparticles such as Lipid-Based Systems employ triggered membrane disruption at pH to release the drugs. Quantum dots and mesoporous silica nanoparticles are examples of inorganic nanoparticles through encapsulation. These systems can enhance medication stability, pharmacokinetics, and therapeutic outcomes while reducing deleterious effects that could result from targeting.