Digital Turbine (APPS -14.24%) stock saw a round of substantial sell-offs Friday. The adtech specialist's share price closed out the daily session down 14.6% amid a 0.3% decline for the S&P 500 index and a 0.6% decline for the Nasdaq Composite index.Following an explosive post-earnings rally for the stock earlier this week, investors sold shares and moved to take profits. In addition to profit-taking action, Digital Turbine stock moved lower due to new restrictions on technology exports and fears that the c ...