Baidu Yi is on the Android operating system and is for the new low cost smart phone for the masses. Apple is on the high end so they are not competing directly in this respect. Apple and Baidu will team up but to what extent we can only guess at this time. No official announcements and a week long Holiday is about to begin so probably not until after. Also, the partnership with Baidu may be different and more extensive than Yandex. Much greater growth and potential in the Chinese market that Apple really wants to penetrate , so you cannot compare share price reaction yet. The deal when it happens could be quite different than the one with Yandex.