This paper describes experiments examining the effect of touching interaction with text in active reading through evaluating the impact of the use of a touch-based tablet device. The first experiment compared the performance of proofreading when using paper and when using a touch-based tablet device. Results showed that participants detected more errors when reading from paper than when reading from the tablet device. During reading, when using paper, participants frequently performed the interaction of text touching, such as pointing to words and sliding their fingers or pens along sentences. This fact suggests that touching interaction with text plays an important role in proofreading tasks. To verify this hypothesis, we conducted a second experiment in which participants proofread documents with constrained interaction with paper. Results showed that they detected more errors when they were allowed to interact with text freely than when they were not allowed to interact with text. Considering these results, we discuss practical implications to effectively support active reading with a touch-based tablet device.