One option for local campaigns on a budget is to use My Maps by Google. This free tool allows campaign teams to overlay voter data onto a Google Map, that can easily be shared and viewed by team members from their mobile device. Each imported file of data will compose a layer over the map. The maximum number of data points that can be imported for any layer is 2,000 rows of data. My Map files are limited to 10 layers. Theoretically, one map could cover as many as 20,000 registered voters.
Each layer can be categorized. One layer might have imported Mountain Voters, another might have imported Independent Voters. Party Designation is generally abbreviated as follows: Democrat-DEM, Libertarian-LIB, Mountain-MTN, Republican-REP. In addition, each layer could constitute an entire ward; this could be done for a small town.
Searches can be made in My Maps. If a volunteer enters “MTN” into the search box, all of the registered Mountain voters would be highlighted (this is assuming party designation was abbreviated in the data file). The highlighted icons / pins may be selected, where an info box will pop-up showing all of the uploaded information of the voter. This is incredibly useful during canvassing. A volunteer can zoom in on the street they are door-knocking and know what type of voter they will encounter (What is their party affiliation?).
Google My Maps: https://www.google.com/mymaps