1. A method for downloading image tile data from a server to a client device, the image tile data being organized, by the server, in a hierarchal structure, where each level of the hierarchal structure stores a subset of image tiles associated with a particular resolution level; the client device including a memory and an output device, the client device being connectable to the server via a communication network, the output device displaying a first image view, the first image view being associated with a first viewport and a first resolution level, the first image view being generated using a portion of the plurality of the first-level image tiles associated with the first resolution level, the portion being determined by the first viewport; the portion of the plurality of the first-level image tiles having been (i) downloaded by the client device from the server and (ii) stored by the client device in the memory to enable rendering thereof; the method being executable by the server; the method comprising: receiving, from the client device, a request for a plurality of second-level image tiles to replace the plurality of first-level image tiles to display a second image view, the second image view being associated with a second view port and a second resolution level, the second resolution level being larger than the first resolution level; each image tile of the plurality of first-level image tiles having four child second-level image tiles within the plurality of second-level image tiles as defined by the hierarchal structure; determining an anchor point of the first image view; based on the anchor point, determining a first anchor image tile of the first-level image tiles; using the hierarchical structure, determining a corresponding four child second-level image tiles, the corresponding four-child second-level image tiles forming a second anchor image tile; sending to the client device the second anchor image tile, the sending configured to cause the client device to: replace, in the memory, the first anchor image tile with the second anchor image tile; replace, on the output device, the first anchor image tile with the second anchor image tile.